The isomorphism problem for commutative monoid rings Original Research Article

By substantial changes and corrections in Demushkinʹs old paper the essentially final positive answer to the isomorphism problem for monoid rings of submonoids of imager is obtained. This means that the underlying monoid is shown to be determined (up to isomorphism) by the corresponding monoid ring. Thereafter the positive answer to the analogous question for the ‘dual’ objects — descrete Hodge algebras — is derived.