diff -r 76ad72736e9e -r f783490c6c99 src/HOL/Analysis/Vitali_Covering_Theorem.thy
--- a/src/HOL/Analysis/Vitali_Covering_Theorem.thy	Wed Jan 31 22:36:12 2024 +0100
+++ b/src/HOL/Analysis/Vitali_Covering_Theorem.thy	Fri Feb 02 11:25:11 2024 +0000
@@ -616,7 +616,7 @@
               apply (subst measure_UNION')
               using that pwC by (auto simp: case_prod_unfold elim: pairwise_mono)
             also have "\<dots> \<le> e"
-              by (metis mult.commute mult.left_neutral mult_le_cancel_iff1 \<open>e > 0\<close> le1)
+              by (metis mult.commute mult.left_neutral mult_le_cancel_right_pos \<open>e > 0\<close> le1)
             finally show ?thesis .
           qed
           have "\<Union>(U ` C) \<in> lmeasurable" "?\<mu> (\<Union>(U ` C)) \<le> e"