diff --git a/bin/tools/named-nzd2nzf.docbook b/bin/tools/named-nzd2nzf.docbook
index c0413312b8..151cd30166 100644
--- a/bin/tools/named-nzd2nzf.docbook
+++ b/bin/tools/named-nzd2nzf.docbook
@@ -72,7 +72,7 @@
   <refsect1>
     <title>SEE ALSO</title>
     <para>
-      <citetitle>BIND 9 Administrator Reference Manual</citetitle>,
+      <citetitle>BIND 9 Administrator Reference Manual</citetitle>
     </para>
   </refsect1>