@article{DE_1968_4_7_a5,
     author = {N. N. Petrov},
     title = {Local controllability of autonomous systems},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1218--1232},
     publisher = {mathdoc},
     volume = {4},
     number = {7},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1968_4_7_a5/}
}