diff --git a/doc/tribool.boostbook b/doc/tribool.boostbook
index ede46f7..1fa199a 100644
--- a/doc/tribool.boostbook
+++ b/doc/tribool.boostbook
@@ -2,7 +2,7 @@
 <!DOCTYPE library PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN"
   "http://www.boost.org/tools/boostbook/dtd/boostbook.dtd">
 <library name="Tribool" dirname="logic" id="tribool"
-         last-revision="$Date: 2004/07/25 03:01:38 $" xmlns:xi="http://www.w3.org/2001/XInclude">
+         last-revision="$Date: 2007/05/03 03:28:53 $" xmlns:xi="http://www.w3.org/2001/XInclude">
   <libraryinfo>
     <author>
       <firstname>Douglas</firstname>
@@ -197,7 +197,7 @@ cout &lt;&lt; boolalpha &lt;&lt; x &lt;&lt; endl; // Prints "maybe"</programlist
 
   </section>
 
-  <xi:include href="reference.boostbook"/>
+  <xi:include href="reference.xml"/>
 
   <testsuite id="tribool.tests">
     <run-test filename="tribool_test.cpp">