diff --git a/source/classes/earthRotation/earthRotation.h b/source/classes/earthRotation/earthRotation.h
index c39625c2..84ced772 100644
--- a/source/classes/earthRotation/earthRotation.h
+++ b/source/classes/earthRotation/earthRotation.h
@@ -42,7 +42,7 @@ typedef std::shared_ptr<EarthRotation> EarthRotationPtr;
 /***** CLASS ***********************************/
 
 /** @brief Transformation between CRF and TRF.
-* An Instance of this class can be created by @ref readConfig. */
+* An Instance of this class can be created by calling the function @ref readConfig(). */
 class EarthRotation
 {
 public:
@@ -78,17 +78,17 @@ class EarthRotation
   * @param[out] S CIO locator [rad]. */
   virtual void earthOrientationParameter(const Time &timeGPS, Double &xp, Double &yp, Double &sp, Double &deltaUT, Double &LOD, Double &X, Double &Y, Double &S) const;
 
-  /** @brief creates an derived instance of this class. */
+  /** @brief Creates a derived instance of this class. */
   static EarthRotationPtr create(Config &config, const std::string &name);
 };
 
 /***** FUNCTIONS *******************************/
 
 /** @brief Creates an instance of the class EarthRotation.
-* Search for a node with @a name in the Config node.
-* if @a name is not found the function returns FALSE and @a earthRotation is untouched.
-* @param config The config node which includes the node with the options for this class
-* @param name Tag name in the config.
+* Search for a node with @a name in the configuration node @a config.
+* If @a name is not found, the function returns FALSE and @a earthRotation is untouched.
+* @param config The configuration node which includes the node @a name with the options for this class
+* @param name Tag name in the configuration node.
 * @param[out] earthRotation Created class.
 * @param mustSet If is MUSTSET and @a name is not found, this function throws an exception instead of returning with FALSE.
 * @param defaultValue Ignored at the moment.
diff --git a/source/classes/earthRotation/earthRotationFile.h b/source/classes/earthRotation/earthRotationFile.h
index 2c4fe6e7..f7fa4141 100755
--- a/source/classes/earthRotation/earthRotationFile.h
+++ b/source/classes/earthRotation/earthRotationFile.h
@@ -2,7 +2,7 @@
 /**
 * @file earthRotationFile.h
 *
-* @brief Interpolated values from file.
+* @brief Interpolates EOPs from input file.
 * @see EarthRotation
 *
 * @author Torsten Mayer-Guerr
@@ -30,7 +30,7 @@ This file can be created with \program{EarthOrientationParameterTimeSeries}.
 
 /***** CLASS ***********************************/
 
-/** @brief According to IERS2010 conventions.
+/** @brief Interpolates EOPs from input file.
 * @ingroup earthRotationGroup
 * @see EarthRotation */
 class EarthRotationFile : public EarthRotation
diff --git a/source/classes/earthRotation/earthRotationIers2003.h b/source/classes/earthRotation/earthRotationIers2003.h
index f50ebb05..88a2b93d 100755
--- a/source/classes/earthRotation/earthRotationIers2003.h
+++ b/source/classes/earthRotation/earthRotationIers2003.h
@@ -48,6 +48,14 @@ from \url{ftp://maia.usno.navy.mil/conv2000/chapter8/}
 /***** CLASS ***********************************/
 
 /** @brief According to IERS2003 conventions.
+ * In addtion to those interpolated values from the input file, 
+ * - diurnal and semi-diurnal variations from ocean tides are considered by the IERS routine \c ORTHO_EOP.F for
+ *   x-pole, y-pole and dUT1
+ * - librations are considered by the routine \c PMSDNUT2.F for x-pole and y-pole
+ * - librations are considered by the routine \c UTLIBR.F for dUT1 and LOD 
+ * 
+ * sp is calculated with the ERFA function \c eraSp00. X,Y, and S are calculated by the 
+ * precession & nutation model with the ERFA function \c eraXys00a.
 * @ingroup earthRotationGroup
 * @see EarthRotation */
 class EarthRotationIers2003 : public EarthRotation
diff --git a/source/classes/earthRotation/earthRotationIers2010.h b/source/classes/earthRotation/earthRotationIers2010.h
index cb66657a..a2eb0088 100755
--- a/source/classes/earthRotation/earthRotationIers2010.h
+++ b/source/classes/earthRotation/earthRotationIers2010.h
@@ -32,6 +32,15 @@ A file with the earth orientation parameter is needed (\configFile{inputfileEOP}
 /***** CLASS ***********************************/
 
 /** @brief According to IERS2010 conventions.
+ * In addtion to those interpolated values from the input file, 
+ * - diurnal and semi-diurnal variations from ocean tides are considered by the IERS routine \c ORTHO_EOP.F for
+ *   x-pole, y-pole and dUT1
+ * - librations are considered by the routine \c PMSDNUT2.F for x-pole and y-pole
+ * - librations are considered by the routine \c UTLIBR.F for dUT1 and LOD 
+ * 
+ * sp is calculated with the ERFA function \c eraSp00. X,Y, and S are calculated either by the truncated 
+ * precession & nutation model with the ERFA function \c eraXys00b or by the untruncated 
+ * precession & nutation model with the ERFA functions \c eraXy06 and \c eraS06.
 * @ingroup earthRotationGroup
 * @see EarthRotation */
 class EarthRotationIers2010 : public EarthRotation
diff --git a/source/classes/earthRotation/earthRotationIers2010b.cpp b/source/classes/earthRotation/earthRotationIers2010b.cpp
index 69f51f81..40158e78 100644
--- a/source/classes/earthRotation/earthRotationIers2010b.cpp
+++ b/source/classes/earthRotation/earthRotationIers2010b.cpp
@@ -105,7 +105,7 @@ void EarthRotationIers2010b::earthOrientationParameter(const Time &timeGPS, Doub
 
     // Models
     // ------
-    // diurnal and semidiurnal variations in EOP (x,y,UT1) from ocean tides
+    // diurnal and semidiurnal variations in EOP (x,y,UT1) and LOD from ocean tides
     if(doodsonEop.doodson.size())
     {
       const Vector thetaf = doodsonMatrix * Doodson::arguments(timeGPS);
diff --git a/source/classes/earthRotation/earthRotationIers2010b.h b/source/classes/earthRotation/earthRotationIers2010b.h
index 80437c3e..6d952df7 100644
--- a/source/classes/earthRotation/earthRotationIers2010b.h
+++ b/source/classes/earthRotation/earthRotationIers2010b.h
@@ -34,6 +34,15 @@ Includes additional high-frequency EOP models (\configFile{inputfileDoodsonEOP}{
 /***** CLASS ***********************************/
 
 /** @brief According to IERS2010 conventions.
+ * In addtion to those interpolated values from the input file, 
+ * - diurnal, semi-diurnal and even higher frequency variations from ocean tides are considered by the 
+ *   input DoodsonEOP file which contains cofficients of corrections for different tidal consituents for 
+ *   x-pole, y-pole, dUT1 and LOD
+ * - librations are considered by the routine \c PMSDNUT2.F for x-pole and y-pole
+ * - librations are considered by the routine \c UTLIBR.F for dUT1 and LOD 
+ * 
+ * sp is calculated with the ERFA function \c eraSp00. X,Y, and S are calculated by the untruncated 
+ * precession & nutation model with the ERFA functions \c eraXy06 and \c eraS06.
 * @ingroup earthRotationGroup
 * @see EarthRotation */
 class EarthRotationIers2010b : public EarthRotation
diff --git a/source/classes/earthRotation/earthRotationZAxis.h b/source/classes/earthRotation/earthRotationZAxis.h
index 6560cc26..5f1b6265 100755
--- a/source/classes/earthRotation/earthRotationZAxis.h
+++ b/source/classes/earthRotation/earthRotationZAxis.h
@@ -53,7 +53,7 @@ inline EarthRotationZAxis::EarthRotationZAxis(Config &config)
 {
   readConfig(config, "initialAngle",    angle0,        Config::MUSTSET, "5.133658456", "Angle at time0 [rad]");
   readConfig(config, "angularVelocity", angleVelocity, Config::MUSTSET, "7.29211585531e-5", "[rad/s]");
-  readConfig(config, "time0",           time0,         Config::MUSTSET, "51740.5", "");
+  readConfig(config, "time0",           time0,         Config::MUSTSET, "51740.5", "Time of the initial angle");
   if(isCreateSchema(config)) return;
 }
 
diff --git a/source/classes/timeSeries/timeSeries.h b/source/classes/timeSeries/timeSeries.h
index 38fb0e14..f5cace7f 100644
--- a/source/classes/timeSeries/timeSeries.h
+++ b/source/classes/timeSeries/timeSeries.h
@@ -45,7 +45,7 @@ typedef std::shared_ptr<TimeSeries> TimeSeriesPtr;
 /***** CLASS ***********************************/
 
 /** @brief Generates time series.
-* An instance of this class can be created with @ref readConfig. */
+* An instance of this class can be created with the function @ref readConfig(). */
 class TimeSeries
 {
   std::vector<TimeSeriesBase*> base;
@@ -60,17 +60,17 @@ class TimeSeries
   /** @brief Time series with increasing order. */
   std::vector<Time> times() const;
 
-  /** @brief creates an derived instance of this class. */
+  /** @brief Creates a derived instance of this class. */
   static TimeSeriesPtr create(Config &config, const std::string &name) {return TimeSeriesPtr(new TimeSeries(config, name));}
 };
 
 /***** FUNCTIONS *******************************/
 
 /** @brief Creates an instance of the class TimeSeries.
-* Search for a node with @a name in the Config node.
-* if @a name is not found the function returns FALSE and a class without times is created.
-* @param config The config node which includes the node with the options for this class
-* @param name Tag name in the config.
+* Search for a node with @a name in the @a config node.
+* if @a name is not found, the function returns FALSE and a class without times is created.
+* @param config The Config node which includes the node with the options for this class
+* @param name Tag name to be searched for in the @a config node.
 * @param[out] timeSeries Created class.
 * @param mustSet If is MUSTSET and @a name is not found, this function throws an exception instead of returning with FALSE.
 * @param defaultValue Ignored at the moment.
diff --git a/source/config/config.h b/source/config/config.h
index 31c5d1b0..fbd85c0a 100644
--- a/source/config/config.h
+++ b/source/config/config.h
@@ -38,30 +38,55 @@ class Config
   enum ComplexType     {CHOICE, SEQUENCE, COMPLEXTYPE};
 
   /** @brief Creates a Configuration from an XML file.
-  * Elements from @a Config can be read with @a readConfig. */
+  * Elements from @a Config can be read with the function @a readConfig(). */
   Config(FileName &fileName, const std::map<std::string, std::string> &commandlineGlobals = std::map<std::string, std::string>());
 
   Config(Config &&)                 = default; //!< Move is allowed
   Config(const Config &)            = delete;  //!< Copy constructor not allowed
   Config &operator=(const Config &) = delete;  //!< Assignment not allowed
 
-  /** @brief Gives the parsed content of the node with @a name. */
+  /** @brief Gives the parsed content of the node with @a name. 
+   * @param name 
+   * @param type 
+   * @param mustSet 
+   * @param defaultValue 
+   * @param annotation Description of this variable.
+   * @param parse 
+   * @param text 
+  */
   Bool getConfigText(const std::string &name, const std::string &type, Config::Appearance mustSet,
                      const std::string &defaultValue, const std::string &annotation, Bool parse, std::string &text);
 
-  /** @brief Gives the parsed content of the node with @a name. */
+  /** @brief Gives the parsed content of the node with @a name. 
+   * @param name 
+   * @param type 
+   * @param mustSet 
+   * @param defaultValue 
+   * @param annotation Description of this variable.
+   * @param v 
+  */
   Bool getConfigValue(const std::string &name, const std::string &type, Config::Appearance mustSet, const std::string &defaultValue, const std::string &annotation, Double &v);
 
-  /** @brief Removes the node with @a name from @a config and stores it in @a conf. */
+  /** @brief Removes the node with @a name from @a config and stores it in @a conf. 
+   * @param name 
+   * @param mustSet 
+   * @param conf
+  */
   Bool getConfig(const std::string &name, Config::Appearance mustSet, Config &conf);
 
   /** @brief Removes all nodes with @a name from @a config and stores it in @a conf.
+   * @param name 
+   * @param conf
+   *
   * The number of elements is unknown as loops and conditions are not evaluated.  */
   Bool getUnboundedConfig(const std::string &name, Config &conf);
 
   /** @brief Reads the first variable(s) @p var.
-  * The nodes are not removed from the config.
-  * Should be used after @a readConfigLater. */
+   * @param var 
+   * @param variableList 
+   * 
+  * The nodes are not removed from this configuration.
+  * Should be used after the function @a readConfigLater(). */
   template<typename T> void read(T &var, VariableList &variableList) const;
 
   /** @brief Gets the current variable list. */
@@ -74,12 +99,19 @@ class Config
   Config();
 
   /** @brief Writes configuration options to an XSD Schema file.
-  * Every program and class will be called. A call to @a readConfig does
+  * Every program and class will be called. A call to the function @a readConfig() does
   * not read any variables but identifies the configuration options.
   * These options will be saved in an XSD Schema file. */
   static void writeSchema(const std::string &fileName);
 
-  /** @brief Registers an element in an XSD Schema. */
+  /** @brief Registers an element in an XSD Schema. 
+   * @param name Name of the element.
+   * @param type Type of the element.
+   * @param mustSet 
+   * @param count
+   * @param defaultValue 
+   * @param annotation Description of this variable.
+  */
   void xselement(const std::string &name, const std::string &type, Config::Appearance mustSet, Config::AppearanceCount count, const std::string &defaultValue, const std::string &annotation);
 
   /** @brief XML node with elements for documentationTable. */
@@ -89,7 +121,7 @@ class Config
   std::string currentNodeName() const;
 
 protected:
-  // Internal class
+  /** @brief Internal class for managing the configuration stack. */
   class StackNode
   {
   public:
@@ -124,7 +156,9 @@ class Config
   void         xscomplexElement(const std::string &name, Config::ComplexType type, Config::Appearance mustSet, const std::string &defaultValue, const std::string &annotation);
   void         addAppInfo(const std::string &text);
 public:
-  void         setNodeUnbounded(); // need access from readConfig(std::vector<T> &var, ...)
+  /** @brief Sets the current node to be unbounded.
+  * This is needed when reading vectors with the function @a readConfig(). */
+  void         setNodeUnbounded();
 
   friend class ProgramConfig;
   friend Bool isCreateSchema(Config &config);
@@ -140,9 +174,9 @@ class Config
 
 /***** CLASS ***********************************/
 
-/** @brief Config elements of a program.
-* It can be read with @a readConfig().
-* The config is evaluated and the program is executed with @a run().
+/** @brief Configuration elements of a program.
+* It can be read with the function @ref readConfig().
+* The config is evaluated and the program is executed with the function @a run().
 * @ingroup configGroup */
 class ProgramConfig : public Config
 {
@@ -153,68 +187,124 @@ class ProgramConfig : public Config
 /***** FUNCTIONS ***********************************/
 
 /** @brief Checks if functions are called in schema mode.
-* No code is allowed except the readConfig functions in schema mode.
+* No code is allowed except for the readConfig() functions in schema mode.
 * @ingroup configGroup */
 Bool isCreateSchema(Config &config);
 
-/** @brief Does Config have an element with @a name?
-* If @a mustSet is MUSTSET and name is not found, an exception is thrown.
+/** @brief Checks if @a config has an element with @a name.
+ * @param config
+ * @param name
+ * @param mustSet
+ *
+* If @a mustSet is MUSTSET and @a name is not found, an exception is thrown.
 * @ingroup configGroup */
 Bool hasName(Config &config, const std::string &name, Config::Appearance mustSet=Config::OPTIONAL);
 
-/** @brief Indicates a renamed config element.
-* Must be called before the @a readConfig functions.
+/** @brief Indicates a renamed configuration element.
+ * @param config
+ * @param oldName
+ * @param newName
+ * @param time
+ *
+* Must be called before the @a readConfig() functions.
 * @ingroup configGroup */
 void renameDeprecatedConfig(Config &config, const std::string &oldName, const std::string &newName, const Time &time);
 
 /** @brief Indicates a renamed choice element.
-* Must be called after @a readConfigChoice and before the @a readConfigChoiceElement functions.
+ * @param config
+ * @param type 
+ * @param oldName
+ * @param newName
+ * @param time
+ *
+* Must be called after the @a readConfigChoice() and before the @a readConfigChoiceElement() functions.
 * @ingroup configGroup */
 void renameDeprecatedChoice(Config &config, std::string &type, const std::string &oldName, const std::string &newName, const Time &time);
 
 /** @brief Starts a group of readConfig elements.
-* If @a mustSet is MUSTSET and name is not found, an exception is thrown.
+ * @param config
+ * @param name
+ * @param mustSet
+ * @param defaultValue
+ * @param annotation Description of this group.
+ *
+* If @a mustSet is MUSTSET and @a name is not found, an exception is thrown.
 * @ingroup configGroup */
 Bool readConfigSequence(Config &config, const std::string &name, Config::Appearance mustSet, const std::string &defaultValue, const std::string &annotation);
 
 /** @brief Ends a group of readConfig elements.
-* Must be called only if the @a readConfigSequence returns TRUE.
+* Must be called only if the function @a readConfigSequence() returns TRUE.
 * @ingroup configGroup */
 void endSequence(Config &config);
 
 /** @brief Starts a choice.
+ * @param config
+ * @param name
+ * @param choice
+ * @param mustSet
+ * @param defaultValue
+ * @param annotation Description of this choice.
+ *
 * If the result is TRUE, the selected choice is given in @a choice.
-* If @a mustSet is MUSTSET and name is not found, an exception is thrown.
+* If @a mustSet is MUSTSET and @a name is not found, an exception is thrown.
 * @ingroup configGroup */
 Bool readConfigChoice(Config &config, const std::string &name, std::string &choice, Config::Appearance mustSet, const std::string &defaultValue, const std::string &annotation);
 
 /** @brief Checks the selected choice.
+ * @param config
+ * @param name  
+ * @param choice
+ * @param annotation Description of this choice.
+ *
 * Returns TRUE if @a name is the selected @a choice.
-* In schema mode all possible @a readConfigChoiceElement must be called.
+* In schema mode, all possible @a readConfigChoiceElement() must be called.
 * @ingroup configGroup */
 Bool readConfigChoiceElement(Config &config, const std::string &name, const std::string &choice, const std::string &annotation="");
 
 /** @brief Ends a group of choice elements.
-* Must be called only if the @a readConfigChoice returns TRUE.
+* Must be called only if the function @a readConfigChoice() returns TRUE.
 * @ingroup configGroup */
 void endChoice(Config &config);
 
 /** @brief Reads a variable from @a config.
-* If @a name is in the @a config, the value is set in @a var and TRUE is returned.
-* If @a name is not in the @a config or the content is empty, FALSE is returned. In this case the value of @a var depends on @a mustSet:
-* @a mustSet = Config::MUSTSET: an exception is thrown.
-* @a mustSet = Config::OPTIONAL: @a var is left untouched and @a defaultValue is not used (@a defaultValue might be set as a hint for groopsGui).
-* @a mustSet = Config::DEFAULT: @a var is set to @a defaultValue (or in case an empty class is created).
+ * @param config The configuration node which includes the variable to be read.
+ * @param name Tag name to be searched for in @a config.
+ * @param var Variable to be read.
+ * @param mustSet 
+ * @param defaultValue Default value for this variable.
+ * @param annotation Description of this variable.
+ * 
+* If @a name is in @a config, the value is set in @a var and TRUE is returned.
+* If @a name is not in @a config or the content is empty, FALSE is returned. In this case the value of @a var depends on @a mustSet:
+* - @a mustSet = Config::MUSTSET, an exception is thrown.
+* - @a mustSet = Config::OPTIONAL, @a var is left untouched and @a defaultValue is not used (@a defaultValue might be set as a hint for groopsGui).
+* - @a mustSet = Config::DEFAULT, @a var is set to @a defaultValue (or in case an empty class is created).
 * @ingroup configGroup */
 template<typename T> Bool readConfig(Config &config, const std::string &name, T &var, Config::Appearance mustSet, const std::string &defaultValue, const std::string &annotation);
 
-/** @brief Removes the config of a variable from @a config and stores it in configNew.
-* It can be later evaluated with configNew.read(). @a var is untouched and only used to determine the type.
+/** @brief Removes the configuration of the variable @a name from @a config and stores it in @a configNew.
+ * @param config The configuration node which includes the variable @a name to be removed.
+ * @param name Name of the variable to be removed from @a config.
+ * @param var Variable 
+ * @param configNew The configuration node where the variable is stored.
+ * @param mustSet 
+ * @param defaultValue 
+ * @param annotation Description of this variable.
+ *
+* It can be later evaluated with the function @a configNew.read(). @a var is untouched and only used to determine the type.
 * @ingroup configGroup */
 template<typename T> Bool readConfigLater(Config &config, const std::string &name, const T &var, Config &configNew, Config::Appearance mustSet, const std::string &defaultValue, const std::string &annotation);
 
-/** @brief Removes the config of a variable from @a config and stores it in configNew.
-* It can be later evaluated with configNew.read(). @a var is untouched and only used to determine the type.
+/** @brief Removes the configuration of the variable @a name from @a config and stores it in @a configNew.
+ * @param config The configuration node which includes the variable @a name to be removed.
+ * @param name Name of the variable to be removed from @a config.
+ * @param var Variable 
+ * @param configNew The configuration node where the variable is stored.
+ * @param mustSet 
+ * @param defaultValue 
+ * @param annotation Description of this variable.
+ *
+* It can be later evaluated with the function @a configNew.read(). @a var is untouched and only used to determine the type.
 * @ingroup configGroup */
 template<typename T> Bool readConfigLater(Config &config, const std::string &name, const std::vector<T> &var, std::vector<Config> &configNew, Config::Appearance mustSet, const std::string &defaultValue, const std::string &annotation);
 
diff --git a/source/programs/conversion/eop/iersC04IAU2000EarthOrientationParameter.cpp b/source/programs/conversion/eop/iersC04IAU2000EarthOrientationParameter.cpp
index 52ffd393..cb16a547 100644
--- a/source/programs/conversion/eop/iersC04IAU2000EarthOrientationParameter.cpp
+++ b/source/programs/conversion/eop/iersC04IAU2000EarthOrientationParameter.cpp
@@ -26,7 +26,15 @@ and write it as \configFile{outputfileEOP}{earthOrientationParameter}.
 
 /***** CLASS ***********************************/
 
-/** @brief Read Earth Orientation Parameter.
+/** @brief Convert an IERS C04 long term EOP file to a GROOPS Earth Orientation Parameter file.
+ * The input IERS C04 long term EOP file can be 
+ * - <a href="https://datacenter.iers.org/versionMetadata.php?filename=latestVersionMeta/254_EOP_C04_20u24.62-NOW254.txt">eopc04.1962-now: sampled values at 00h UT / dX, dY IAU2000</a>
+ * - <a href="https://datacenter.iers.org/versionMetadata.php?filename=latestVersionMeta/255_EOP_C04_20u24.12h.84-NOW255.txt">eopc04.1984-now: sampled values at 12h UT / dX, dY IAU2000</a>
+ * - <a href="https://datacenter.iers.org/versionMetadata.php?filename=latestVersionMeta/256_EOP_C04_20u24_dPsi_dEps_62-NOW_IAU2000256.txt">eopc04.1962-now: sampled values at 00h UT / dPsi, dEps IAU2000</a>
+ * - <a href="https://datacenter.iers.org/versionMetadata.php?filename=latestVersionMeta/257_EOP_C04_20u24_12h_dPsi_dEps_62-NOW_IAU2000257.txt">eopc04.1984-now: sampled values at 12h UT / dPsi, dEps IAU2000</a>
+ * 
+ * which theoretically should be the same only differing in start dates, sampling clocks and CPO conventions and all can be downloaded from the 
+ * <a href="https://www.iers.org/IERS/EN/DataProducts/EarthOrientationData/eop.html">IERS website</a>.
 * @ingroup programsConversionGroup */
 class IersC04IAU2000EarthOrientationParameter
 {
@@ -49,8 +57,8 @@ void IersC04IAU2000EarthOrientationParameter::run(Config &config, Parallel::Comm
 
     readConfig(config, "outputfileEOP", outName,   Config::MUSTSET,  "", "");
     readConfig(config, "inputfile",     inName,    Config::MUSTSET,  "", "");
-    readConfig(config, "timeStart",     timeStart, Config::OPTIONAL, "", "");
-    readConfig(config, "timeEnd",       timeEnd,   Config::OPTIONAL, "", "");
+    readConfig(config, "timeStart",     timeStart, Config::OPTIONAL, "", "Start time of EOPs to read (inclusive). Default: MJD 0");
+    readConfig(config, "timeEnd",       timeEnd,   Config::OPTIONAL, "", "End time of EOPs to read (inclusive). Default: Date 9999-01-01");
     if(isCreateSchema(config)) return;
 
     // Erdrotationsparameter einlesen
@@ -73,6 +81,7 @@ void IersC04IAU2000EarthOrientationParameter::run(Config &config, Parallel::Comm
     std::vector<Double> mjd, xp, yp, du, ld, dX, dY;
     while(std::getline(file, line))
     {
+      // skip header or comment lines which start with '#'
       if(String::startsWith(line, "#"))
         continue;
 
diff --git a/source/programs/conversion/eop/iersHighFrequentEop2DoodsonEop.cpp b/source/programs/conversion/eop/iersHighFrequentEop2DoodsonEop.cpp
index 62498c5c..1cf81d63 100644
--- a/source/programs/conversion/eop/iersHighFrequentEop2DoodsonEop.cpp
+++ b/source/programs/conversion/eop/iersHighFrequentEop2DoodsonEop.cpp
@@ -26,7 +26,23 @@ and write them as \configFile{outputfileDoodsonEOP}{doodsonEarthOrientationParam
 /***** CLASS ***********************************/
 
 /** @brief Read Diurnal and Subdiurnal Earth Orientation variations.
-* @ingroup programsConversionGroup */
+ * Except for comment lines (starting with '#'), the data format of each line from the input file should be:
+ * 
+ * <tt>name gamma l lp F D Omega Doodson_number period xp_sin xp_cos yp_sin yp_cos UT1_sin UT1_cos LOD_sin LOD_cos</tt>
+ * 
+ * where 
+ * - \b name name of the tidal constituent, e.g. "M2"
+ * - <b> gamma l, lp, F, D, Omega</b> Fundamental arguments (Delaunay arguments) of nutation
+ * - \b Doodson_number Doodson number of the tidal constituent, e.g. "255.555" for M2
+ * - \b period period of the tidal constituent
+ * - <b> xp_sin, xp_cos</b> Coefficients of sine and cosine term for x pole coordinate in micro arc seconds
+ * - <b> yp_sin, yp_cos</b> Coefficients of sine and cosine term for y pole coordinate in micro arc seconds
+ * - <b> UT1_sin, UT1_cos</b> Coefficients of sine and cosine term for UT1 in micro seconds
+ * - <b> LOD_sin, LOD_cos</b> Coefficients of sine and cosine term for LOD in micro seconds
+ * 
+ * For every data line, all fields are necessary. The tide name @a name, if no conventional 
+ * one available, can be arbitrary character strings, just for the purpose of placeholder. 
+ * @ingroup programsConversionGroup */
 class IersHighFrequentEop2DoodsonEop
 {
 public:
diff --git a/source/programs/conversion/eop/iersRapidIAU2000EarthOrientationParameter.cpp b/source/programs/conversion/eop/iersRapidIAU2000EarthOrientationParameter.cpp
index 9e402fd6..df085104 100644
--- a/source/programs/conversion/eop/iersRapidIAU2000EarthOrientationParameter.cpp
+++ b/source/programs/conversion/eop/iersRapidIAU2000EarthOrientationParameter.cpp
@@ -25,7 +25,24 @@ and write it as \configFile{outputfileEOP}{earthOrientationParameter}.
 
 /***** CLASS ***********************************/
 
-/** @brief Read Earth Orientation Parameter.
+/** @brief Convert an IERS Standard or Daily Rapid EOP file to a GROOPS Earth Orientation Parameter file.
+ * The input IERS Rapid EOP file can be 
+ * <a href="https://datacenter.iers.org/versionMetadata.php?filename=latestVersionMeta/9_FINALS.ALL_IAU2000_V2013_019.txt">finals.all (IAU2000)</a>, 
+ * <a href="https://datacenter.iers.org/versionMetadata.php?filename=latestVersionMeta/10_FINALS.DATA_IAU2000_V2013_0110.txt">finals.data (IAU2000)</a> or
+ * <a href="https://datacenter.iers.org/versionMetadata.php?filename=latestVersionMeta/13_FINALS.DAILY_IAU2000_V2013_0113.txt">finals.daily (IAU2000)</a> 
+ * from the <a href="https://www.iers.org/IERS/EN/DataProducts/EarthOrientationData/eop">IERS website</a>.
+ * They both share the same <a href="https://maia.usno.navy.mil/ser7/readme.finals2000A">format</a>. 
+ * 
+ * Not like indicated by the name, this program can read both IAU2000- and IAU1980-baed EOP data as the format is the same for both.
+ * Therefore, the input IERS Rapid EOP file can also be 
+ * <a href="https://datacenter.iers.org/versionMetadata.php?filename=latestVersionMeta/7_FINALS.ALL_IAU1980_V2013_017.txt">finals.all (IAU1980)</a>, 
+ * <a href="https://datacenter.iers.org/versionMetadata.php?filename=latestVersionMeta/8_FINALS.DATA_IAU1980_V2013_018.txt">finals.data (IAU1980)</a> or
+ * <a href="https://datacenter.iers.org/versionMetadata.php?filename=latestVersionMeta/12_FINALS.DAILY_IAU1980_V2013_0112.txt">finals.daily (IAU1980)</a>.
+ * Format specification for those files can be found <a href="https://maia.usno.navy.mil/ser7/readme.finals">here</a>. Just note that, 
+ * the Celestial Pole Offsets would be dPSI & dEPSILON instead of dX & dY when using the IAU1980-based EOP data as input.
+ * 
+ * Only EOP data from Bulletin A are read and converted though both Bulletin A and 
+ * Bulletin B data are available in those IERS Rapid EOP files.
 * @ingroup programsConversionGroup */
 class IersRapidIAU2000EarthOrientationParameter
 {
@@ -48,9 +65,9 @@ void IersRapidIAU2000EarthOrientationParameter::run(Config &config, Parallel::Co
     Time timeEnd   = date2time(9999,1,1);
 
     readConfig(config, "outputfileEOP", outName,   Config::MUSTSET,  "", "");
-    readConfig(config, "inputfile",     inName,    Config::MUSTSET,  "", "");
-    readConfig(config, "timeStart",     timeStart, Config::OPTIONAL, "", "");
-    readConfig(config, "timeEnd",       timeEnd,   Config::OPTIONAL, "", "");
+    readConfig(config, "inputfile",     inName,    Config::MUSTSET,  "", "IERS Rapid EOP file");
+    readConfig(config, "timeStart",     timeStart, Config::OPTIONAL, "", "Start time of EOPs to read (inclusive). Default: MJD 0");
+    readConfig(config, "timeEnd",       timeEnd,   Config::OPTIONAL, "", "End time of EOPs to read (inclusive). Default: Date 9999-01-01");
     if(isCreateSchema(config)) return;
 
     // Erdrotationsparameter einlesen
@@ -73,17 +90,24 @@ void IersRapidIAU2000EarthOrientationParameter::run(Config &config, Parallel::Co
       if((time<timeStart)||(time>timeEnd))
         continue;
 
+      // Bull. A PM-x (sec. of arc)
       _xp = getDouble(line.substr( 18,  9),xp);
+      // Bull. A PM-y (sec. of arc)
       _yp = getDouble(line.substr( 37,  9),yp);
+      // Bull. A UT1-UTC (sec. of time)
       _du = getDouble(line.substr( 58, 10),du);
+      // Bull. A LOD (msec. of time) -- NOT ALWAYS FILLED
       _ld = getDouble(line.substr( 79,  7),ld,1e3);
+      // Bull. A dX (msec. of arc)
       _dX = getDouble(line.substr( 97,  9),dX,1e3);
+      // Bull. A dY (msec. of arc)
       _dY = getDouble(line.substr(116,  9),dY,1e3);
 
       mjd.push_back(_mjd);
       xp.push_back(_xp);
       yp.push_back(_yp);
       du.push_back(_du);
+      // convert from msec to sec
       ld.push_back(_ld*1e-3);
       dX.push_back(_dX*1e-3);
       dY.push_back(_dY*1e-3);
diff --git a/source/programs/conversion/eop/igs2EarthOrientationParameter.cpp b/source/programs/conversion/eop/igs2EarthOrientationParameter.cpp
index 75ae7671..b756a2d5 100644
--- a/source/programs/conversion/eop/igs2EarthOrientationParameter.cpp
+++ b/source/programs/conversion/eop/igs2EarthOrientationParameter.cpp
@@ -25,7 +25,16 @@ and write it as \configFile{outputfileEOP}{earthOrientationParameter}.
 
 /***** CLASS ***********************************/
 
-/** @brief Earth Orientation Parameter from IGS daily file.
+/** @brief Convert one or several IGS daily Earth Rotation Parameter (ERP) file(s) to a GROOPS Earth Orientation Parameter file.
+ * The input IGS daily ERP file(s) should be in the format "version 2", as described in 
+ * <a href="https://lists.igs.org/pipermail/igsmail/1998/003315.html?_gl=1*1xa369f*_ga*MjkxNzcxMzAyLjE3NzEyNDY4MjM.*_ga_Z5RH7R682C*czE3NzMzMjYyOTYkbzUkZzEkdDE3NzMzMjgwMDckajU3JGwwJGgw&_ga=2.96939671.964448877.1773324318-291771302.1771246823">IGSMAIL-1943</a>.
+ * Note that, as the first 9 lines of all input ERP files are regarded as header and will be skipped, the program will not
+ * work with IGS weekly ERP files though they share the same format for data lines. 
+ * And when feeding multiple files, it is the user's responsibility to make sure that 
+ * those input files are in the correct chronological order. This program does not sort the 
+ * data records before writing them into the output GROOPS EOP file.
+ * 
+ * As no CPOs included in IGS ERP files, the output GROOPS EOP file will have CPOs values of 0.0.
 * @ingroup programsConversionGroup */
 class Igs2EarthOrientationParameter
 {
@@ -47,9 +56,9 @@ void Igs2EarthOrientationParameter::run(Config &config, Parallel::CommunicatorPt
     Time timeStart, timeEnd = date2time(9999,1,1);
 
     readConfig(config, "outputfileEOP", outName,    Config::MUSTSET,  "", "");
-    readConfig(config, "inputfile",     fileNameIn, Config::MUSTSET,  "", "");
-    readConfig(config, "timeStart",     timeStart,  Config::OPTIONAL, "", "");
-    readConfig(config, "timeEnd",       timeEnd,    Config::OPTIONAL, "", "");
+    readConfig(config, "inputfile",     fileNameIn, Config::MUSTSET,  "", "IGS daily ERP files");
+    readConfig(config, "timeStart",     timeStart,  Config::OPTIONAL, "", "Start time of ERPs to read (inclusive). Default: MJD 0");
+    readConfig(config, "timeEnd",       timeEnd,    Config::OPTIONAL, "", "End time of ERPs to read (inclusive). Default: Date 9999-01-01");
     if(isCreateSchema(config)) return;
 
     logStatus<<"read input files"<<Log::endl;
diff --git a/source/programs/conversion/iers2OceanPoleTide.cpp b/source/programs/conversion/iers2OceanPoleTide.cpp
index e495d48f..c0b3ad01 100644
--- a/source/programs/conversion/iers2OceanPoleTide.cpp
+++ b/source/programs/conversion/iers2OceanPoleTide.cpp
@@ -27,6 +27,12 @@ and convert into \file{oceanPoleTide file}{oceanPoleTide}.
 /***** CLASS ***********************************/
 
 /** @brief Read ocean pole tide model.
+ * The input file contains the coefficients of a self-consistent equilibrium ocean pole tide model
+ *  according to the IERS conventions, as described in the Section 6.5 of the IERS Conventions (2010).
+ * An example of a such ocean pole tide model is from Desai (2002), the coefficients of which can be found 
+ * at ftp://tai.bipm.org/iers/conv2010/chapter6/desaiscopolecoef.txt. 
+ * The input deformation coefficients (Love numbers) should cover the maximum degree for the ocean 
+ * pole tide model as specified via @a maxDegree.
 * @ingroup programsConversionGroup */
 class Iers2OceanPoleTide
 {
@@ -48,8 +54,8 @@ void Iers2OceanPoleTide::run(Config &config, Parallel::CommunicatorPtr /*comm*/)
     UInt   maxDegree;
 
     readConfig(config, "outputfileOceanPole",        outputName,     Config::MUSTSET, "",                "");
-    readConfig(config, "inputfile",                  inputName,      Config::MUSTSET, "",                "");
-    readConfig(config, "inputfileLoadingLoveNumber", loveNumberName, Config::MUSTSET, "{groopsDataDir}/loading/loadLoveNumbers_Gegout97.txt", "");
+    readConfig(config, "inputfile",                  inputName,      Config::MUSTSET, "",                "coefficients of the ocean pole tide model");
+    readConfig(config, "inputfileLoadingLoveNumber", loveNumberName, Config::MUSTSET, "{groopsDataDir}/loading/loadLoveNumbers_Gegout97.txt", "load deformation coefficients");
     readConfig(config, "maxDegree",                  maxDegree,      Config::MUSTSET, "",                "");
     readConfig(config, "GM",                         GM,             Config::DEFAULT, STRING_DEFAULT_GM, "Geocentric gravitational constant");
     readConfig(config, "R",                          R,              Config::DEFAULT, STRING_DEFAULT_R,  "Reference radius");