&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;
In order to translate public identifiers into local system identifiers,
&lt;application&gt;Jade&lt;/application&gt; and &lt;application&gt;SP&lt;/application&gt; read the catalog files
pointed to by &lt;envar&gt;SGML_CATALOG_FILES&lt;/envar&gt;.
&lt;/para&gt;