@article{ZNSL_1968_7_a6,
     author = {N. N. Ural'tseva},
     title = {Degenerating quasilinear systems of elliptic type},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {184--222},
     publisher = {mathdoc},
     volume = {7},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1968_7_a6/}
}