2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/31666Every endofunctor of the category of classes is proved to be set-based in the sense of Aczel and Mendler, therefore, it has a final coalgebra. Other basic properties of these endofunctors are proved, e.g. the existence of a free completely iterative theory.Logic in Computer ScienceF.4.1text