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@article{DE_1986_22_9_a17, author = {E. S. Gubanova}, title = {A problem in the theory of second-order elliptic equations in the plane}, journal = {Differencialʹnye uravneni\^a}, pages = {1609--1610}, publisher = {mathdoc}, volume = {22}, number = {9}, year = {1986}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1986_22_9_a17/} }
E. S. Gubanova. A problem in the theory of second-order elliptic equations in the plane. Differencialʹnye uravneniâ, Tome 22 (1986) no. 9, pp. 1609-1610. http://geodesic.mathdoc.fr/item/DE_1986_22_9_a17/