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@article{IVM_1964_4_a10, author = {L. P. Kokhanovskaya}, title = {On the accuracy of the first approximation for non-stationary linear systems}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {75--78}, publisher = {mathdoc}, number = {4}, year = {1964}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1964_4_a10/} }
L. P. Kokhanovskaya. On the accuracy of the first approximation for non-stationary linear systems. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 4 (1964), pp. 75-78. http://geodesic.mathdoc.fr/item/IVM_1964_4_a10/