2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/166133We give a short argument showing that if $m, n \in {1, 2, ...} \cup ω$, then the groups mV and nV are not isomorphic. This answers a question of Brin.7 pages, 2 figuresGroup TheoryGeneral Topology20E32; 20B22; 20F65; 20F38text