diff --git a/docs/zenmap.xml b/docs/zenmap.xml
index b413ec4b3..b0c1f647a 100644
--- a/docs/zenmap.xml
+++ b/docs/zenmap.xml
@@ -1,5 +1,3 @@
-<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
-          "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
 <refentry id='man-zenmap1'>
   <refmeta>
     <refentrytitle>zenmap</refentrytitle>