These header files and the file suppl_s.lib are from
The SUPPL package; a supplemental library written by
Copyright (C) 1995-97 Steffen Kaiser, Release Version 2.6

This library is available from the Steffen's site at
ftp://www.inf.fh-rhein-sieg.de/pub/freedos/local/suppl26.zip

It is also mirrored at http://www.gcfl.net/freedos/suppl/suppl26.zip
