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@article{DAN_1971_200_5_a1, author = {W. Gerisch}, title = {A remark on the work of {N.\,K.~Bari} on biorthogonal systems and bases in {Hilbert} space}, journal = {Doklady Akademii Nauk}, pages = {1018--1019}, publisher = {mathdoc}, volume = {200}, number = {5}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1971_200_5_a1/} }
W. Gerisch. A remark on the work of N.\,K.~Bari on biorthogonal systems and bases in Hilbert space. Doklady Akademii Nauk, Tome 200 (1971) no. 5, pp. 1018-1019. http://geodesic.mathdoc.fr/item/DAN_1971_200_5_a1/