<?xml version="1.0" encoding="UTF-8"?>
<book xml:id="book" xmlns="http://docbook.org/ns/docbook" version="5.0">

  <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="book/bookinfo.xml"/>
  <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="book/dedication.xml"/>
  <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="book/preface.xml"/>

  <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="content/tables.xml"/>

  <!-- Appendices -->
  <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="appendix/cc.xml"/> 
  <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="appendix/mit.xml"/>
  <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="appendix/glossary.xml"/>

  <index/>

</book>

<?xml version="1.0" encoding="UTF-8"?>
<book xml:id="book" xmlns="http://docbook.org/ns/docbook" version="5.0">

  <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="book/bookinfo.xml"/>
  <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="book/dedication.xml"/>
  <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="book/preface.xml"/>

  <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="content/tables.xml"/>

  <!-- Appendices -->
  <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="appendix/cc.xml"/> 
  <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="appendix/mit.xml"/>
  <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="appendix/glossary.xml"/>

  <index/>

</book>

Switch to 2003 namespace of XInclude
Switch to 2003 namespace of XInclude
