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@article{IVM_2002_1_a3, author = {S. A. Gusarenko}, title = {On conditions for the positive-definiteness of operators in a {Hilbert} space}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {17--20}, publisher = {mathdoc}, number = {1}, year = {2002}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_2002_1_a3/} }
S. A. Gusarenko. On conditions for the positive-definiteness of operators in a Hilbert space. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 1 (2002), pp. 17-20. http://geodesic.mathdoc.fr/item/IVM_2002_1_a3/