--- a/src/HOL/UNITY/Comp/Priority.thy Sat Jan 05 17:00:43 2019 +0100
+++ b/src/HOL/UNITY/Comp/Priority.thy Sat Jan 05 17:24:33 2019 +0100
@@ -254,8 +254,8 @@
text\<open>We have proved all (relevant) theorems given in the paper. We didn't
-assume any thing about the relation @{term r}. It is not necessary that
-@{term r} be a priority relation as assumed in the original proof. It
+assume any thing about the relation \<^term>\<open>r\<close>. It is not necessary that
+\<^term>\<open>r\<close> be a priority relation as assumed in the original proof. It
suffices that we start from a state which is finite and acyclic.\<close>