You can download ABACUS from: http://www.informatik.uni-koeln.de/ls_juenger/projects/abacus.html
ABACUS is being further developed. New releases are announced
to all users that obtained a license (see Section 
).
If you wish to receive these news without being already
an official user, or if you want to be removed from this list, send a
message to:
abacus@informatik.uni-koeln.de