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@article{IVM_1988_11_a7, author = {G. I. Russu}, title = {The spectrum of an operator in a~couple of {Banach} spaces}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {42--49}, publisher = {mathdoc}, number = {11}, year = {1988}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1988_11_a7/} }
G. I. Russu. The spectrum of an operator in a~couple of Banach spaces. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 11 (1988), pp. 42-49. http://geodesic.mathdoc.fr/item/IVM_1988_11_a7/