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@article{IVM_1959_2_a8, author = {P. N. Knyazev}, title = {On the use of minimax properties in perturbation theory}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {94--100}, publisher = {mathdoc}, number = {2}, year = {1959}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1959_2_a8/} }
P. N. Knyazev. On the use of minimax properties in perturbation theory. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 2 (1959), pp. 94-100. http://geodesic.mathdoc.fr/item/IVM_1959_2_a8/