diff -r ecc99a5a1ab8 -r 4eb431c3f974 src/HOL/Semiring_Normalization.thy
--- a/src/HOL/Semiring_Normalization.thy	Tue Oct 10 22:18:58 2017 +0100
+++ b/src/HOL/Semiring_Normalization.thy	Mon Oct 09 19:10:47 2017 +0200
@@ -5,7 +5,7 @@
 section \<open>Semiring normalization\<close>
 
 theory Semiring_Normalization
-imports Numeral_Simprocs Nat_Transfer
+imports Numeral_Simprocs
 begin
 
 text \<open>Prelude\<close>