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@article{DE_1987_23_12_a23, author = {O. Ya. Savchenko}, title = {On the eigenvalues of the {Schr\"odinger} equation}, journal = {Differencialʹnye uravneni\^a}, pages = {2168}, publisher = {mathdoc}, volume = {23}, number = {12}, year = {1987}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1987_23_12_a23/} }
O. Ya. Savchenko. On the eigenvalues of the Schr\"odinger equation. Differencialʹnye uravneniâ, Tome 23 (1987) no. 12. http://geodesic.mathdoc.fr/item/DE_1987_23_12_a23/