[tex-k] revtex/bibtex titles in references

[Karl Berry]

    Do you know of a work-around?

How about simply 
title = "Whatever ... {$\Delta$} ...",
or am I missing something?  BibTeX will leave stuff in braces alone.
(You don't need the \mbox either, e.g., title = "About {G}reen's Theorem".)

    Sorry---you've exceeded BibTeX's buffer size 5000

It's hardwired in the binary.  We could increase it, but there must be
something quite funky going on if it thinks the lines in your source are
longer than 5000 characters.  Can you send your actual .bib and .tex?

Best,
Karl