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@article{IVM_1978_10_a8, author = {A. I. Pulatov}, title = {A~criterion for the orthogonality of a~system of trigonometric polynomials}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {56--60}, publisher = {mathdoc}, number = {10}, year = {1978}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1978_10_a8/} }
A. I. Pulatov. A~criterion for the orthogonality of a~system of trigonometric polynomials. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 10 (1978), pp. 56-60. http://geodesic.mathdoc.fr/item/IVM_1978_10_a8/