A STRONG CANCELLATION THEOREM FOR MODULES OVER C∞×Cq

The module cancellation problem asks whether, given modules X, X′ and Y over a ring Λ, the existence of an isomorphism X⊕Y≅⁡X′⊕Y implies that X≅⁡X′. When q is prime we prove a strong cancellation property for certain modules over ℤ[C∞×Cq], generalizing, in part, the strong cancellation property for modules over ℤ[Cq] established by R. Wiegand (1984).