The Free On-line Dictionary of Computing (30 December 2018):

SWI-Prolog

    A Prolog by Jan Wielemaker
    like a superset of Edinburgh Prolog.
   Version 1.7.2.  Docking Station is distributed under General
   Public License.  It runs on Sun-4, Sun-3, Linux, DEC
   MIPS (incomplete), RS/6000, PS2/AIX, Atari ST,
   Gould PN, NeXT, VAX, HP-UX (problems), MS-DOS, and
   OS/2.

   (ftp://swi.psy.uva.nl/pub/SWI-Prolog).

   OS/2 (ftp://mpii02999.ag2.mpi-sb.mpg.de/pub/toolw/SWI/).

   Mailing list: prolog-request@swi.psy.uva.nl.

   (2000-03-23)