diff --git a/documentation/adt-manual/adt-intro.xml b/documentation/adt-manual/adt-intro.xml
index 9ae908fc11..83fe3094e6 100644
--- a/documentation/adt-manual/adt-intro.xml
+++ b/documentation/adt-manual/adt-intro.xml
@@ -1,5 +1,6 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
-"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
+[<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
 
 <chapter id='adt-intro'>