diff --git a/man2/ioperm.2 b/man2/ioperm.2
index febc1c3ae..e9b172f50 100644
--- a/man2/ioperm.2
+++ b/man2/ioperm.2
@@ -120,4 +120,5 @@ and in
 Avoid the latter, it is available on i386 only.
 .SH SEE ALSO
 .BR iopl (2),
+.BR outb (2),
 .BR capabilities (7)