2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/65313We obtain a result concerning the stability under the interpolation with functional parameter method for the approximation spaces of Lorentz-Marcinkiewicz type and also for the approximation spaces generated by symmetric norming functions of a certain type.Operator Algebras47A57, 47B06, 47B10 (Primary) 47L20 (Secondary)text