@article{DE_1973_9_5_a2,
     author = {G. M. Begalishvili},
     title = {The optimal control problem under constraints on the phase coordinates},
     journal = {Differencialʹnye uravneni\^a},
     pages = {807--814},
     publisher = {mathdoc},
     volume = {9},
     number = {5},
     year = {1973},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1973_9_5_a2/}
}