From the W3C Weekly News - 16 November 2003 e-mailing:
MathML Working Group Notes Published
The Math Working Group has released "Units in MathML," "Structured
Types in MathML 2.0" and "Bound Variables in MathML" as Working Group
Notes. MathML is an XML application that allows mathematical notation
and content to be served, received and processed on the Web. Visit the
Math home page.