@article{DE_1994_30_11_a12,
     author = {A. V. Pukhlikov},
     title = {Liouville's theorem in optimal control problems},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1958--1965},
     publisher = {mathdoc},
     volume = {30},
     number = {11},
     year = {1994},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1994_30_11_a12/}
}