Documentation for VPL and PL file formats?

["Melissa O'Neill" <oneill@cs.sfu.ca>]

I'm wondering if there is documentation somewhere that describes the
format of VPL and PL files. In trying to assess the performance of both
fontinst and afmtotfm, and it'd be very useful if I had some kind of
description of VPL and PL (and for that matter TFM and VF files).

With such documentation at my disposal, I might get to know whether it'd
be worth my while to re-write some or all of fontinst in Perl, write a
post-processor for afmtotfm or just leave all these things well alone.

I'm crossing my fingers that this information wasn't just published in
some old TUGboat article and nowhere else, since tracking down copies
of TUGboat turns out to be quite a challenge for me here.

Curious as ever,

    Melissa.

P.S. Does anyone have an ISSN for TUGboat, or doesn't it have one?