@article{DE_1970_6_1_a15,
     author = {G. N. Yakovlev},
     title = {Weak solutions of second order quasilinear elliptic systems},
     journal = {Differencialʹnye uravneni\^a},
     pages = {157--163},
     publisher = {mathdoc},
     volume = {6},
     number = {1},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1970_6_1_a15/}
}