@article{DE_1973_9_3_a23,
     author = {L. E. Zabello},
     title = {On the theory of the controllability of linear nonstationary systems},
     journal = {Differencialʹnye uravneni\^a},
     pages = {563--564},
     publisher = {mathdoc},
     volume = {9},
     number = {3},
     year = {1973},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1973_9_3_a23/}
}