diff --git a/man/ack.texi b/man/ack.texi
index 2b76a7073d8..29279c4b4e1 100644
--- a/man/ack.texi
+++ b/man/ack.texi
@@ -74,6 +74,9 @@ contributed ERC, an advanced Internet Relay Chat client.
 @item
 Boaz Ben-Zvi wrote @file{profile.el}, to time Emacs Lisp functions.
 
+@item
+Anna M. Bigatti wrote @file{cal-html.el}, which produces HTML calendars.
+
 @item
 Ray Blaak wrote @file{delphi.el}, a major mode for editing Delphi
 (Object Pascal) source code.