2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/71590We study totally geodesic codimension 1 smooth foliations on Lorentzian manifold. We are in particular interested by the relations between riemannian flows and geodesic foliations. We prove that, up to a 2-cover, any Seifert bundle admit such a foliation.18 pages, in frenchDifferential Geometry57R30; 53C50text