2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/142484We construct a non-free but aleph_1-separable, torsion-free abelian group G with a pure free subgroup B such that all subgroups of G disjoint from B are free and such that G/B is divisible. This answers a question of Irwin and shows that a theorem of Blass and Irwin cannot be strengthened so as to give an exact analog for torsion-free groups of a result proved for p-groups by Benabdallah and Irwin.LogicGroup TheoryBasic Subgroups and Freeness, A Counterexampletext