@article{AFM_2009_34_1_a2,
     author = {Giovanni Alessandrini and Vincenzo Nesi},
     title = {Beltrami operators, non-symmetric elliptic equations and quantitative {Jacobian} bounds},
     journal = {Annales Fennici Mathematici},
     pages = {47--67},
     publisher = {mathdoc},
     volume = {34},
     number = {1},
     year = {2009},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AFM_2009_34_1_a2/}
}