src/HOL/Library/Library.thy

--- a/src/HOL/Library/Library.thy	Thu Jun 12 18:02:39 2014 +0200
+++ b/src/HOL/Library/Library.thy	Thu Jun 12 21:23:28 2014 +0200
@@ -64,6 +64,7 @@
   Sublist
   Sum_of_Squares
   Transitive_Closure_Table
+  Tree
   While_Combinator
 begin
 end