Some Notes on the Baer-Invariant of a Nilpotent Product of Groups,

W. Haebich (1972, Bull. Austral. Math. Soc.7, 279–296) presented a formula for the Schur multiplier of a regular product of groups. In this paper, first, it is shown that the Baer-invariant of a nilpotent product of groups with respect to the variety of nilpotent groups has a homomorphic image and in finite case a subgroup of Haebichʹs type. Second, a formula will be presented for the Baer-invariant of a nilpotent product of cyclic groups with respect to the variety of nilpotent groups.