@article{MMO_1963_12_a3,
     author = {M. I. Vishik},
     title = {Quasi-linear strongly elliptic systems of differential equations of divergence form},
     journal = {Trudy Moskovskogo matemati\v{c}eskogo ob\^{s}estva},
     pages = {125--184},
     publisher = {mathdoc},
     volume = {12},
     year = {1963},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MMO_1963_12_a3/}
}