@article{ZNSL_1974_39_a8,
     author = {V. A. Solonnikov},
     title = {On differential properties of weak solutions of quasilinear equations},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {110--119},
     publisher = {mathdoc},
     volume = {39},
     year = {1974},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1974_39_a8/}
}