%0 Journal Article %A Gonzalo Contreras %T Geodesic flows with positive topological entropy, twist maps and hyperbolicity %J Annals of mathematics %D 2010 %P 761-808 %V 172 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4007/annals.2010.172.761/ %R 10.4007/annals.2010.172.761 %G en %F 10_4007_annals_2010_172_761