diff --git a/share/man/man4/ch.4 b/share/man/man4/ch.4
index 7ff9e8d1adea..a306fff7238e 100644
--- a/share/man/man4/ch.4
+++ b/share/man/man4/ch.4
@@ -1,4 +1,4 @@
-.\"	$Id$
+.\"	$Id: ch.4,v 1.10 1997/02/22 13:24:25 peter Exp $
 .\" Copyright (c) 1996
 .\"	Julian Elischer <julian@freebsd.org>.  All rights reserved.
 .\"
@@ -101,6 +101,7 @@ device entries
 .Sh DIAGNOSTICS
 None.
 .Sh SEE ALSO
+.Xr chio 1 ,
 .Xr cd 4 ,
 .Xr sd 4 ,
 .Xr st 4