1 files changed, 3 insertions, 0 deletions
diff --git a/time.c b/time.c
index dd1c0d88d1..881264d927 100644
--- a/time.c
+++ b/time.c
@@ -640,6 +640,9 @@ gmtimev(VALUE timev, struct vtm *result)
 static struct tm *localtime_with_gmtoff(const time_t *t, struct tm *result, long *gmtoff);
 
 /*
+ * The idea is come from Perl:
+ * http://use.perl.org/articles/08/02/07/197204.shtml
+ *
  * compat_common_month_table is generated by following program.
  * This table finds the last month which start the same day of a week.
  * The year 2037 is not used because