@article{DAN_1970_195_2_a6,
     author = {V. R. Portnov},
     title = {The first boundary value problem for a certain class of quasilinear systems of equations that have divergence form},
     journal = {Doklady Akademii Nauk},
     pages = {285--288},
     publisher = {mathdoc},
     volume = {195},
     number = {2},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1970_195_2_a6/}
}