Almost commensurability of 3-dimensional Anosov flows

Two flows are almost commensurable if, up to removing finitely many periodic orbits and taking finite coverings, they are topologically equivalent. We prove that all suspensions of automorphisms of the 2-dimensional torus and all geodesic flows on unit tangent bundles to hyperbolic 2-orbifolds are pairwise almost commensurable. (C) 2013 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.