&lt;!DOCTYPE para PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
          "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"&gt;
&lt;para&gt;
The equation 
&lt;informalequation&gt;
  &lt;alt&gt;e^(pi*i) + 1 = 0&lt;/alt&gt;
  &lt;graphic fileref="figures/epi10.png"/&gt;
&lt;/informalequation&gt;
is delightful because it joins together five of the most
important mathematical constants.
&lt;/para&gt;