src/Pure/ROOT

--- a/src/Pure/ROOT	Tue Nov 20 13:44:06 2018 +0100
+++ b/src/Pure/ROOT	Tue Nov 20 13:46:13 2018 +0100
@@ -1,9 +1,9 @@
 chapter Pure
 
 session Pure =
-  description \<open>
-    The Pure logical framework
-\<close>
+  description "
+    The Pure logical framework.
+  "
   options [threads = 1, export_theory]
   theories
     Pure (global)