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@article{DE_1974_10_4_a2, author = {L. T. Ashchepkov and D. S. \`Eppel'}, title = {An analogue of {Kelley's} condition in optimal systems with lag}, journal = {Differencialʹnye uravneni\^a}, pages = {591--597}, publisher = {mathdoc}, volume = {10}, number = {4}, year = {1974}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1974_10_4_a2/} }
L. T. Ashchepkov; D. S. Èppel'. An analogue of Kelley's condition in optimal systems with lag. Differencialʹnye uravneniâ, Tome 10 (1974) no. 4, pp. 591-597. http://geodesic.mathdoc.fr/item/DE_1974_10_4_a2/