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@article{IVM_1973_5_a4, author = {I. P. Kostenko}, title = {Criteria for the perfectness of {K\"othe} sequence spaces}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {28--39}, publisher = {mathdoc}, number = {5}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1973_5_a4/} }
I. P. Kostenko. Criteria for the perfectness of K\"othe sequence spaces. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 5 (1973), pp. 28-39. http://geodesic.mathdoc.fr/item/IVM_1973_5_a4/