--- a/src/LCF/ex/Ex3.thy Thu Jul 23 14:20:51 2015 +0200
+++ b/src/LCF/ex/Ex3.thy Thu Jul 23 14:25:05 2015 +0200
@@ -1,4 +1,4 @@
-section {* Addition with fixpoint of successor *}
+section \<open>Addition with fixpoint of successor\<close>
theory Ex3
imports "../LCF"