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@article{DE_1990_26_8_a20, author = {B. M. Usifov and Z. A. Karagezov}, title = {On the problem of the existence of optimal controls}, journal = {Differencialʹnye uravneni\^a}, pages = {1437--1441}, publisher = {mathdoc}, volume = {26}, number = {8}, year = {1990}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1990_26_8_a20/} }
B. M. Usifov; Z. A. Karagezov. On the problem of the existence of optimal controls. Differencialʹnye uravneniâ, Tome 26 (1990) no. 8, pp. 1437-1441. http://geodesic.mathdoc.fr/item/DE_1990_26_8_a20/