diff -r c03edebe7408 -r 06e9aff51d17 src/HOL/Number_Theory/Cong.thy
--- a/src/HOL/Number_Theory/Cong.thy	Mon Nov 16 14:32:35 2009 +0000
+++ b/src/HOL/Number_Theory/Cong.thy	Mon Nov 16 17:22:10 2009 +0000
@@ -20,7 +20,7 @@
 
 The original theory, "IntPrimes", by Thomas M. Rasmussen, defined and
 developed the congruence relations on the integers. The notion was
-extended to the natural numbers by Chiaeb. Jeremy Avigad combined
+extended to the natural numbers by Chaieb. Jeremy Avigad combined
 these, revised and tidied them, made the development uniform for the
 natural numbers and the integers, and added a number of new theorems.