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@article{DE_1978_14_10_a7, author = {L. M. Kuperman}, title = {On the theory of $\varepsilon $-controllability of linear systems with lag}, journal = {Differencialʹnye uravneni\^a}, pages = {1791--1795}, publisher = {mathdoc}, volume = {14}, number = {10}, year = {1978}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1978_14_10_a7/} }
L. M. Kuperman. On the theory of $\varepsilon $-controllability of linear systems with lag. Differencialʹnye uravneniâ, Tome 14 (1978) no. 10, pp. 1791-1795. http://geodesic.mathdoc.fr/item/DE_1978_14_10_a7/