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@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/} }
G. N. Yakovlev. Weak solutions of second order quasilinear elliptic systems. Differencialʹnye uravneniâ, Tome 6 (1970) no. 1, pp. 157-163. http://geodesic.mathdoc.fr/item/DE_1970_6_1_a15/