@article{AIHPC_2020__37_1_181_0, author = {De Philippis, G. and Pratelli, A.}, title = {The closure of planar diffeomorphisms in {Sobolev} spaces}, journal = {Annales de l'I.H.P. Analyse non lin\'eaire}, pages = {181--224}, publisher = {Elsevier}, volume = {37}, number = {1}, year = {2020}, doi = {10.1016/j.anihpc.2019.08.001}, mrnumber = {4049920}, zbl = {1446.46018}, language = {en}, url = {http://www.numdam.org/articles/10.1016/j.anihpc.2019.08.001/} }