2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/148462We extend the Wald cosmic no-hair theorem to a general class of scalar-tensor nonminimally coupled theories of gravity where ordinary matter is also present in the form of a perfect fluid. We give a set of conditions for obtaining a de Sitter expansion independently of any initial conditions, generalizing the treatment of such a problem as given by Wald. Finally we apply the results to some specific models.13 pages, Latex, submitted to Phys. Lett. AAstrophysicstext