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@article{DE_1973_9_3_a23, author = {L. E. Zabello}, title = {On the theory of the controllability of linear nonstationary systems}, journal = {Differencialʹnye uravneni\^a}, pages = {563--564}, publisher = {mathdoc}, volume = {9}, number = {3}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1973_9_3_a23/} }
L. E. Zabello. On the theory of the controllability of linear nonstationary systems. Differencialʹnye uravneniâ, Tome 9 (1973) no. 3, pp. 563-564. http://geodesic.mathdoc.fr/item/DE_1973_9_3_a23/