  The DifSets package for GAP implements an algorithm for enumerating all
difference sets in a group up to equivalence and provides access to a library
of results. The algorithm functions by finding difference sums, which are
potential images of difference sets in quotient groups of the original group,
and searching their preimages. In this way, the search space can be
dramatically decreased, and searches of groups of relatively large order (such
as order 64 or order 96) can be completed.
