Matsumoto, YukioMontesinos Amilibia, José María2023-06-202023-06-2019910387-387010.3836/tjm/1270130498https://hdl.handle.net/20.500.14352/58616The authors prove that every geometric orbifold is good. More precisely, let X be a smooth connected manifold, and let G be a group of diffeomorphisms of X with the property that if any two elements of G agree on a nonempty open subset of X, then they coincide on X. If Q is an orbifold which is locally modelled on quotients of open subsets of X by finite subgroups of G, then the authors prove that the universal orbifold covering of Q is a (G,X)-manifold. A similar theorem was stated, and the proof sketched, in W. Thurston's lecture notes on the geometry and topology of 3-manifolds.engjournal articlehttp://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.tjm/1270130498http://projecteuclid.org/DPubS?Service=UI&version=1.0&verb=Display&handle=euclidrestricted access515.1finite group actionorbifold coveringgeometryTopologíaGeometría1210 Topología1204 Geometría