diff --git a/.gitattributes b/.gitattributes
index e7c1d93..5ef7f98 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,2 +1,3 @@
 # Auto detect text files and perform LF normalization
 * text eol=lf
+*.pdf binary
diff --git a/specs/vcalendar-10.pdf b/specs/vcalendar-10.pdf
new file mode 100644
index 0000000..9a3bee9
Binary files /dev/null and b/specs/vcalendar-10.pdf differ
diff --git a/specs/vcard-21.pdf b/specs/vcard-21.pdf
new file mode 100644
index 0000000..9926d05
Binary files /dev/null and b/specs/vcard-21.pdf differ