diff --git a/share/sgml/man-refs.ent b/share/sgml/man-refs.ent
index eddaf8378d..cc6179a61b 100644
--- a/share/sgml/man-refs.ent
+++ b/share/sgml/man-refs.ent
@@ -3495,6 +3495,7 @@
 <!ENTITY man.ng.rfc1490.4 "<citerefentry/<refentrytitle/ng_rfc1490/<manvolnum/4//">
 <!ENTITY man.ng.socket.4 "<citerefentry/<refentrytitle/ng_socket/<manvolnum/4//">
 <!ENTITY man.ng.sppp.4 "<citerefentry/<refentrytitle/ng_sppp/<manvolnum/4//">
+<!ENTITY man.ng.tag.4 "<citerefentry/<refentrytitle/ng_tag/<manvolnum/4//">
 <!ENTITY man.ng.tcpmss.4 "<citerefentry/<refentrytitle/ng_tcpmss/<manvolnum/4//">
 <!ENTITY man.ng.tee.4 "<citerefentry/<refentrytitle/ng_tee/<manvolnum/4//">
 <!ENTITY man.ng.tty.4 "<citerefentry/<refentrytitle/ng_tty/<manvolnum/4//">