diff -r a75d71c73362 -r 9f90ac19e32b src/HOL/Library/BigO.thy
--- a/src/HOL/Library/BigO.thy	Thu Jun 26 10:06:54 2008 +0200
+++ b/src/HOL/Library/BigO.thy	Thu Jun 26 10:07:01 2008 +0200
@@ -6,7 +6,7 @@
 header {* Big O notation *}
 
 theory BigO
-imports Main SetsAndFunctions
+imports Plain Presburger SetsAndFunctions
 begin
 
 text {*