Dear Forum,

What is a good way in GAP3 of computing with finitely generated (but
not necessarily finite) abelian groups? The things I need to do now is
determine structure efficiently when I have very many relations (even
forming FreeGroup(n)/rels can pack up) and to work efficiently with a
quotient (by a given subgroup).

Or should I be working in GAP4?

Many thanks.

Leonard.