Mathematical Markup Language V2.0 DTD

 The Mathematical Markup Language (MathML) V2.0 is an XML
 application for describing mathematical notation
 and capturing both its structure and content.
 The docbook-mathml package allows you to generate output
 documents from source files that use MathML markup.
 .
 Includes a prototype extension of the XHTML 1.1 DTD
 that incorporates MathML 2.0.