<?xml version="1.0"?>
<chapter>
  <p>a simple test</p>
  <p>multiple tests</p>
  <p>a diff<em>i</em>cult one</p>
  <p><p>a span</p>n<p>ing one</p></p>
  <p><p>and an unbal</p><empty/>anced test</p>
  <p>for empty string <seq>123</seq></p>
  <p id="1">a<b>b</b>c</p>
  <p id="2"><!--X-->abc</p>
</chapter>
