diff -r d80b2df54d31 -r a96320074298 src/HOL/Quickcheck_Random.thy
--- a/src/HOL/Quickcheck_Random.thy	Sun Jan 06 13:44:33 2019 +0100
+++ b/src/HOL/Quickcheck_Random.thy	Sun Jan 06 15:04:34 2019 +0100
@@ -209,8 +209,8 @@
 
 subsection \<open>Deriving random generators for datatypes\<close>
 
-ML_file "Tools/Quickcheck/quickcheck_common.ML"
-ML_file "Tools/Quickcheck/random_generators.ML"
+ML_file \<open>Tools/Quickcheck/quickcheck_common.ML\<close>
+ML_file \<open>Tools/Quickcheck/random_generators.ML\<close>
 
 
 subsection \<open>Code setup\<close>