pacemaker/doc/Pacemaker_Explained/en-US/Preface.xml

<?xml version='1.0' encoding='utf-8' ?>
<!DOCTYPE preface PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
]>
<preface><title>Preface</title>
  <xi:include href="Common_Content/Conventions.xml" xmlns:xi="http://www.w3.org/2001/XInclude"/>
  <xi:include href="Feedback.xml" xmlns:xi="http://www.w3.org/2001/XInclude">
    <xi:fallback xmlns:xi="http://www.w3.org/2001/XInclude">
      <xi:include href="Common_Content/Feedback.xml" xmlns:xi="http://www.w3.org/2001/XInclude"/>
    </xi:fallback>
  </xi:include>
</preface>