 &lt;log/&gt;
        &lt;logbase&gt;
          &lt;cn&gt; 3 &lt;/cn&gt;
        &lt;/logbase&gt;
        &lt;ci&gt; x &lt;/ci&gt;
      &lt;/apply&gt;
    &lt;/math&gt;
  &lt;/body&gt;
&lt;/html&gt;
</pre>
</div>

<p>The following example shows the way in which XHTML 1.0 markup
could be incorporated into another XML namespace:</p>

<div class="good">
<pre>
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;!-- initially, the default namespace is "books" --&gt;
&lt;book xmlns='urn:loc.gov:books'
    xmlns:isb