diff --git a/lectures/_config.yml b/lectures/_config.yml
index e3cc624..cf9ebff 100644
--- a/lectures/_config.yml
+++ b/lectures/_config.yml
@@ -94,15 +94,28 @@ sphinx:
         
       launch_buttons:
         colab_url                 : https://colab.research.google.com
-    intersphinx_mapping: {
-      'intro':    [https://intro.quantecon.org/, null],
-      'dle':      [https://quantecon.github.io/lecture-dle/, null],
-      'dps':      [https://quantecon.github.io/lecture-dps/, null],
-      'eqm':      [https://quantecon.github.io/lecture-eqm/, null],
-      'stats':    [https://quantecon.github.io/lecture-stats/, null],
-      'tools':    [https://quantecon.github.io/lecture-tools-techniques/, null],
-      'dynam':    [https://quantecon.github.io/lecture-dynamics/, null]
-      }
+    intersphinx_mapping:
+      intro: 
+        - https://intro.quantecon.org/
+        - null
+      dle:
+        - https://quantecon.github.io/lecture-dle/
+        - null
+      dps:
+        - https://quantecon.github.io/lecture-dps/
+        - null
+      eqm:
+        - https://quantecon.github.io/lecture-eqm/
+        - null
+      stats:
+        - https://quantecon.github.io/lecture-stats/
+        - null
+      tools:
+        - https://quantecon.github.io/lecture-tools-techniques/
+        - null
+      dynam:
+        - https://quantecon.github.io/lecture-dynamics/
+        - null
     mathjax3_config:
       tex:
         macros:
diff --git a/lectures/intro.mda b/lectures/intro.mda
deleted file mode 100644
index 0b55249..0000000
--- a/lectures/intro.mda
+++ /dev/null
@@ -1,24 +0,0 @@
----
-jupytext:
-  text_representation:
-    extension: .md
-    format_name: myst
-kernelspec:
-  display_name: Python 3
-  language: python
-  name: python3
----
-
-# Advanced Dynamic Programming
-
-This website presents a set of lectures on a modeling technique called dynamic programming squared, designed and written by
-[Thomas J. Sargent](http://www.tomsargent.com/) and [John Stachurski](http://johnstachurski.net/).
-
-For an overview of the series, see [this page](https://quantecon.org/python-lectures/)
-
-```{tableofcontents}
-```
-
-```{admonition} Previous website
-While this new site will receive all future updates, you may still view the [old site here](http://rst-python-advanced.quantecon.org) for the next month.
-```
\ No newline at end of file