diff -r 2b3772ecfdec -r e6784939d645 src/HOL/Data_Structures/Tree23_Map.thy
--- a/src/HOL/Data_Structures/Tree23_Map.thy	Mon Nov 16 12:37:46 2015 +0100
+++ b/src/HOL/Data_Structures/Tree23_Map.thy	Mon Nov 16 13:08:52 2015 +0100
@@ -120,7 +120,7 @@
 
 interpretation T23_Map: Map_by_Ordered
 where empty = Leaf and lookup = lookup and update = update and delete = delete
-and inorder = inorder and wf = bal
+and inorder = inorder and inv = bal
 proof (standard, goal_cases)
   case 2 thus ?case by(simp add: lookup)
 next