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@article{DE_1977_13_3_a0, author = {N. K. Alekseev}, title = {Some questions on the controllability of two-dimensional systems}, journal = {Differencialʹnye uravneni\^a}, pages = {387--397}, publisher = {mathdoc}, volume = {13}, number = {3}, year = {1977}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1977_13_3_a0/} }
N. K. Alekseev. Some questions on the controllability of two-dimensional systems. Differencialʹnye uravneniâ, Tome 13 (1977) no. 3, pp. 387-397. http://geodesic.mathdoc.fr/item/DE_1977_13_3_a0/