diff --git a/share/sgml/man-refs.ent b/share/sgml/man-refs.ent
index a3e8be7ebc..654872035f 100644
--- a/share/sgml/man-refs.ent
+++ b/share/sgml/man-refs.ent
@@ -3498,6 +3498,7 @@
 <!ENTITY man.snd.ds1.4 "<citerefentry/<refentrytitle/snd_ds1/<manvolnum/4//">
 <!ENTITY man.snd.emu10k1.4 "<citerefentry/<refentrytitle/snd_emu10k1/<manvolnum/4//">
 <!ENTITY man.snd.es137x.4 "<citerefentry/<refentrytitle/snd_es137x/<manvolnum/4//">
+<!ENTITY man.snd.ess.4 "<citerefentry/<refentrytitle/snd_ess/<manvolnum/4//">
 <!ENTITY man.snd.gusc.4 "<citerefentry/<refentrytitle/snd_gusc/<manvolnum/4//">
 <!ENTITY man.snd.maestro3.4 "<citerefentry/<refentrytitle/snd_maestro3/<manvolnum/4//">
 <!ENTITY man.snd.sbc.4 "<citerefentry/<refentrytitle/snd_sbc/<manvolnum/4//">