diff --git a/doc/MPD-Protocol.xml b/doc/MPD-Protocol.xml
index a61003577..1a4800424 100644
--- a/doc/MPD-Protocol.xml
+++ b/doc/MPD-Protocol.xml
@@ -1,5 +1,5 @@
 <?xml version='1.0' encoding='UTF-8'?>
-<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "docbook/xml-dtd-4.2-1.0-24/docbookx.dtd" []>
+<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" []>
 <article>
   <title>MPD Protocol</title>
   <articleinfo>