@article{10_4007_annals_2016_184_2_5,
     author = {Artur Avila and Jacopo De Simoi and Vadim Kaloshin},
     title = {An integrable deformation of an ellipse of small eccentricity is an ellipse},
     journal = {Annals of mathematics},
     pages = {527--558},
     publisher = {mathdoc},
     volume = {184},
     number = {2},
     year = {2016},
     doi = {10.4007/annals.2016.184.2.5},
     mrnumber = {3548532},
     zbl = {06662219},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4007/annals.2016.184.2.5/}
}