ch. The <a href="exclude"><code>exclude</code></a> directory
contains separate, independent RELAX NG schemas that enforce
exclusions.  To check use of exclusions, a document should be
validated against each of these schemas that is applicable <strong>in
addition to</strong> being validated against the RELAX NG XHTML schema
proper. The available schemas are as follows:

<dl>

<dt><a href="exclude/basic.rng"><code>exclude/basic.rng</code></a></dt>
<dd>checks the exclusions relating to <code>a</code>