We construct a commutative version of the group ring and show that it allows
one to translate questions about the normal generation of groups into questions
about the generation of ideals in commutative rings. We demonstrate this with
an alternative proof of a result about the normal generation of the free
product of two cyclic groups.Comment: 31 pages, preprint. Reason for revision: additions to content; in
particular rewritten Section 5 and new Section 6 adde