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@article{IVM_1966_5_a12, author = {R. M. Nasyrov}, title = {Qualitative study of a~singular case of stability in the case of two zero-roots}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {100--111}, publisher = {mathdoc}, number = {5}, year = {1966}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1966_5_a12/} }
R. M. Nasyrov. Qualitative study of a~singular case of stability in the case of two zero-roots. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 5 (1966), pp. 100-111. http://geodesic.mathdoc.fr/item/IVM_1966_5_a12/