The two MOP spec documents were provided to me by Digital of Canada in
1990 when I was writing the RSTS/E MOP server for them. I have cleaned
them up so they render properly with a modern version of Adobe Acrobat
(they were originally designed to be sent as-is to DEC PostScript print-
ers, which were far more forgiving of bad PostScript files.

The LAT protocol specification materials are from Bitsavers, until I dig
out and scan my much cleaner copies:
http://www.bitsavers.org/pdf/dec/ethernet/lat/