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@article{DE_2000_36_4_a7, author = {A. F. Filippov}, title = {Stability and instability by the first approximation}, journal = {Differencialʹnye uravneni\^a}, pages = {475--485}, publisher = {mathdoc}, volume = {36}, number = {4}, year = {2000}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_2000_36_4_a7/} }
A. F. Filippov. Stability and instability by the first approximation. Differencialʹnye uravneniâ, Tome 36 (2000) no. 4, pp. 475-485. http://geodesic.mathdoc.fr/item/DE_2000_36_4_a7/