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@article{DE_1974_10_5_a11, author = {G. Ya. Shafranov}, title = {Generation of periodic motions from an equilibrium state with purely imaginary roots}, journal = {Differencialʹnye uravneni\^a}, pages = {860--872}, publisher = {mathdoc}, volume = {10}, number = {5}, year = {1974}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1974_10_5_a11/} }
G. Ya. Shafranov. Generation of periodic motions from an equilibrium state with purely imaginary roots. Differencialʹnye uravneniâ, Tome 10 (1974) no. 5, pp. 860-872. http://geodesic.mathdoc.fr/item/DE_1974_10_5_a11/