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@article{MZM_1971_9_1_a3, author = {Yu. V. Pokornyi}, title = {Inequality for second characteristic values of positive operators of certain classes}, journal = {Matemati\v{c}eskie zametki}, pages = {27--33}, publisher = {mathdoc}, volume = {9}, number = {1}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1971_9_1_a3/} }
Yu. V. Pokornyi. Inequality for second characteristic values of positive operators of certain classes. Matematičeskie zametki, Tome 9 (1971) no. 1, pp. 27-33. http://geodesic.mathdoc.fr/item/MZM_1971_9_1_a3/