Montesinos Amilibia, José María2023-06-202023-06-2020031139-1138https://hdl.handle.net/20.500.14352/58659It is proved that any closed orientable 3-manifold is a 3-fold irregular branched covering of the 3-sphere branched over a wildly embedded knot. These branched coverings are obtained by starting with such a branched covering over a tame knot and then inserting into it a particular irregular branched covering of the 3-sphere over the 3-sphere, with a wild branch set. It is also shown how to use related techniques to produce branched coverings of certain open 3-manifolds over tame, properly embedded arcs in R3. For example, the Whitehead contractible open 3-manifold is expressible as a 2-fold branched covering over such an arc, conjecturally in uncountably many different ways. These results should be considered as illustrations of the general construction given in the author's recent paper [Rev. Mat. Complut. 15 (2002), no. 2, 533–542engjournal articlehttp://www.mat.ucm.es/serv/revmat/vol16-2m.htmlhttp://www.springer.com/restricted access515.162Wild knotsopen manifoldsbranched coverings.Topología1210 Topología