--- a/src/Doc/System/Sessions.thy Mon Dec 09 12:22:23 2013 +0100
+++ b/src/Doc/System/Sessions.thy Mon Dec 09 12:27:18 2013 +0100
@@ -139,7 +139,7 @@
quasi-hierarchic naming conventions like @{text "HOL\<dash>SPARK"},
@{text "HOL\<dash>SPARK\<dash>Examples"}. An alternative is to use
unqualified names that are relatively long and descriptive, as in
- the Archive of Formal Proofs (@{url "http://afp.sf.net"}), for
+ the Archive of Formal Proofs (@{url "http://afp.sourceforge.net"}), for
example. *}