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@article{DAN_1962_146_1_a8, author = {A. S. Markus}, title = {Eigenvalues and singular values of the sum and product of linear operators}, journal = {Doklady Akademii Nauk}, pages = {34--36}, publisher = {mathdoc}, volume = {146}, number = {1}, year = {1962}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1962_146_1_a8/} }
A. S. Markus. Eigenvalues and singular values of the sum and product of linear operators. Doklady Akademii Nauk, Tome 146 (1962) no. 1, pp. 34-36. http://geodesic.mathdoc.fr/item/DAN_1962_146_1_a8/