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@article{IVM_1981_8_a9, author = {V. M. Shashkov}, title = {An existence theorem for an extremal problem in {a~Hilbert} space}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {52--54}, publisher = {mathdoc}, number = {8}, year = {1981}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1981_8_a9/} }
V. M. Shashkov. An existence theorem for an extremal problem in a~Hilbert space. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 8 (1981), pp. 52-54. http://geodesic.mathdoc.fr/item/IVM_1981_8_a9/