<mathref> – “odd” reference of a formula

Attributes:

refid

ID of the equation you want to reference (required)

Possible Contents: (Text | inline element)*

Description: See <ref>, but <mathref> only works for equations that have been labeled using the first column of an <mlabeledtr>. Actually such an equation should also have a real id, so you don't need <mathref>. It's just to make MathML support a little bit more complete.

(I needed an extra element for this kind of reference because I really wanted to be able to point to such equations, but for validation issues refid can't be of type ID, but must be CDATA.)