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@article{DAN_1957_117_3_a3, author = {Z. I. Leibenzon}, title = {On estimation of the eigenvalues of self-adjoint operators}, journal = {Doklady Akademii Nauk}, pages = {371--373}, publisher = {mathdoc}, volume = {117}, number = {3}, year = {1957}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1957_117_3_a3/} }
Z. I. Leibenzon. On estimation of the eigenvalues of self-adjoint operators. Doklady Akademii Nauk, Tome 117 (1957) no. 3, pp. 371-373. http://geodesic.mathdoc.fr/item/DAN_1957_117_3_a3/