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@article{DE_1973_9_12_a8, author = {E. L. Tonkov}, title = {Disconjugacy and number of switchings in a linear time-optimal nonstationary system}, journal = {Differencialʹnye uravneni\^a}, pages = {2180--2185}, publisher = {mathdoc}, volume = {9}, number = {12}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1973_9_12_a8/} }
E. L. Tonkov. Disconjugacy and number of switchings in a linear time-optimal nonstationary system. Differencialʹnye uravneniâ, Tome 9 (1973) no. 12, pp. 2180-2185. http://geodesic.mathdoc.fr/item/DE_1973_9_12_a8/