2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/139038We give, for each non self-dual Wadge class C contained in the class of the Gdelta sets, a characterization of Borel sets which are not potentially in C, among Borel sets with countable vertical sections; to do this, we use results of partial uniformization.LogicGeneral Topology03E15, 54H05text