Use Case TREE: Sample Data

<book>....
<section><title>Intro</title><p>Text...</p>
  <section><title>And First</title><p>Text...</p>
  <image source="map.gif"><p>Text..</p>
    <section><title>Meanwhile</title><p>Text...</p>
    ...
    </section>
  </section>
</section>
</book>