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@article{IVM_1965_2_a1, author = {B. E. Veits}, title = {Bessel and {Hilbert} systems in {Banach} spaces and questions of stability}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {7--23}, publisher = {mathdoc}, number = {2}, year = {1965}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1965_2_a1/} }
B. E. Veits. Bessel and Hilbert systems in Banach spaces and questions of stability. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 2 (1965), pp. 7-23. http://geodesic.mathdoc.fr/item/IVM_1965_2_a1/