2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/100881C. Gordon conjectured that a connected sum of two Heegaard splittings is stabilized if and only if one of the two factors is stabilized (Problem 3.91 in Kirby's problem list). In this paper, we shall prove this conjecture.79 pages, 26 figuresGeometric Topologytext