[texhax] LaTeX tool for theorem/proof cross-references?

[Lorna Stewart]

I'm looking for a program that, given a LaTeX file (containing lots of 
\label and \ref commands, and lots of theorems and proofs), outputs 
information about which proofs reference which theorems/lemmas/etc, in 
the form of a directed graph, perhaps along with some information about 
items that are not referenced, most referenced items, longest paths, 
etc. Does anyone know of such a tool?
Any pointers would be appreciated, thanks,
Lorna Stewart
U of Alberta, Canada
stewart at cs.ualberta.ca