fixed a small error, daniel
diff --git a/doc/xml.html b/doc/xml.html
index c33f1d2..03d0dae 100644
--- a/doc/xml.html
+++ b/doc/xml.html
@@ -1514,7 +1514,7 @@
 content are done in a single declaration. Similary the following declares
 <code>div1</code> elements:</p>
 
-<p><code>&lt;!ELEMENT div1 (head, (p | list | note)*, div2*)&gt;</code></p>
+<p><code>&lt;!ELEMENT div1 (head, (p | list | note)*, div2?)&gt;</code></p>
 
 <p>means div1 contains one <code>head</code> then a series of optional
 <code>p</code>, <code>list</code>s and <code>note</code>s and then an