2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/146571In this paper we give a positive answer to a question of Nash concerning the arc space of a singularity, for the class of quasi-ordinary hypersurface singularities, extending to this case previous results and techniques of Shihoko Ishii.comments and references addedAlgebraic Geometry14J17; 32S10, 14M25text