I thought it came from USG, as it was definitely in PWB 3.0 [which was "rebranded" as System III post break-up], I think it may have been in PWB 2.0. Mashey might remember. I'll check any doc I have at home tonight, but do not think I still have PWB 2.0 bits anywhere. I think Warren has a TAR image from Henry of the PWB 1.0 which to check.