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@article{DAN_1962_142_5_a3, author = {A. D. Dzhuraev}, title = {A general linear boundary-value problem for the equation $\Delta u\pm\lambda c(x,y)u=0$}, journal = {Doklady Akademii Nauk}, pages = {994--997}, publisher = {mathdoc}, volume = {142}, number = {5}, year = {1962}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1962_142_5_a3/} }
A. D. Dzhuraev. A general linear boundary-value problem for the equation $\Delta u\pm\lambda c(x,y)u=0$. Doklady Akademii Nauk, Tome 142 (1962) no. 5, pp. 994-997. http://geodesic.mathdoc.fr/item/DAN_1962_142_5_a3/