diff --git a/ChangeLog b/ChangeLog
index 24e35776c9..7661cd7f78 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,6 @@
 Sat Jul 23 21:14:00 2011  Tadayoshi Funaba  <tadf@dotrb.org>
 
-	* lib/cmath.rb: should return a real number if possible.
+	* lib/cmath.rb (cbrt): should return a real number if possible.
 
 Sat Jul 23 20:12:52 2011  NARUSE, Yui  <naruse@ruby-lang.org>