chromium/content/test/data/accessibility/html/nestedlist.html

<p> This is a multi-leveled list </p>
<ol>
  <li> Sports
    <ol>
      <li> Tennis </li>
      <li> basketball </li>
    </ol>
  </li>
  <li> Books
    <ol>
      <li> Oliver Twist </li>
      <li> Kindred </li>
      <li> The Promise of Sleep </li>
    </ol>
  </li>
  <li> Recipes </li>
  <ol>
  </ol>
</ol>