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@article{DE_1971_7_8_a10, author = {V. S. Vinogradov}, title = {A boundary value problem for a first order elliptic equation on the plane}, journal = {Differencialʹnye uravneni\^a}, pages = {1440--1448}, publisher = {mathdoc}, volume = {7}, number = {8}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1971_7_8_a10/} }
V. S. Vinogradov. A boundary value problem for a first order elliptic equation on the plane. Differencialʹnye uravneniâ, Tome 7 (1971) no. 8, pp. 1440-1448. http://geodesic.mathdoc.fr/item/DE_1971_7_8_a10/