diff -r 48d935524988 -r c5d0fdc260fa src/HOL/Library/Quotient_Set.thy
--- a/src/HOL/Library/Quotient_Set.thy	Mon Apr 11 15:07:15 2016 +0200
+++ b/src/HOL/Library/Quotient_Set.thy	Mon Apr 11 15:26:58 2016 +0200
@@ -5,7 +5,7 @@
 section \<open>Quotient infrastructure for the set type\<close>
 
 theory Quotient_Set
-imports Main Quotient_Syntax
+imports Quotient_Syntax
 begin
 
 subsection \<open>Contravariant set map (vimage) and set relator, rules for the Quotient package\<close>