--- a/doc/book/en/21-appendix.en.txt	Wed Nov 19 17:05:34 2008 -0800
+++ b/doc/book/en/21-appendix.en.txt	Wed Nov 19 17:35:20 2008 -0800
@@ -13,4 +13,5 @@
    21-03-modules-stdlib.en.txt
    21-04-modules-cbw-api.en.txt
    21-05-mercurial.en.txt
+   21-06-mercurial-forest.en.txt