@article{10_4153_CJM_2013_001_7,
     author = {Cruz, Victor and Mateu, Joan and Orobitg, Joan},
     title = {Beltrami {Equation} with {Coefficient} in {Sobolev} and {Besov} {Spaces}},
     journal = {Canadian journal of mathematics},
     pages = {1217--1235},
     year = {2013},
     volume = {65},
     number = {6},
     doi = {10.4153/CJM-2013-001-7},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-2013-001-7/}
}