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@article{IVM_1988_9_a0, author = {V. A. Andrienko}, title = {Summability of orthogonal series by {Ces\`aro} methods of negative order}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {3--10}, publisher = {mathdoc}, number = {9}, year = {1988}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1988_9_a0/} }
V. A. Andrienko. Summability of orthogonal series by Ces\`aro methods of negative order. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 9 (1988), pp. 3-10. http://geodesic.mathdoc.fr/item/IVM_1988_9_a0/