--- a/src/ZF/ex/Group.thy Fri Jun 17 11:35:35 2005 +0200
+++ b/src/ZF/ex/Group.thy Fri Jun 17 16:12:49 2005 +0200
@@ -5,7 +5,7 @@
header {* Groups *}
-theory Group = Main:
+theory Group imports Main begin
text{*Based on work by Clemens Ballarin, Florian Kammueller, L C Paulson and
Markus Wenzel.*}