1<p>An <abbr title="Abbreviation">ABBR</abbr>: "<abbr title="Reference">REF</abbr>".
2ref and REFERENCE should be ignored.</p>
3<p>The <abbr title="Hyper Text Markup Language">HTML</abbr> specification
4is maintained by the <abbr title="World Wide Web Consortium">W3C</abbr>.</p>