See section "2.8 Prolog and Document Type Declaration" in the "Extensible Markup Language (XML) 1.0 (Second Edition)" here.

You might also like to follow on with Create XML from Schema. The modules XML::LibXML and SGML::DTDParse may help too. Note that I've not used these modules, they just came up when I Super Searched "XML DTD" in SoPW.

Oh, and finding someone close by who knows XML will help.

DWIM is Perl's answer to Gödel

In reply to Re: Parsing an XML-like definition of an XML-like language to create a parser of the actual data in that language. by GrandFather
in thread Parsing an XML-like definition of an XML-like language to create a parser of the actual data in that language. by Moron

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