@article{IVM_1976_12_a3,
     author = {L. E. Zabello},
     title = {On the question of the controllability of nonstationary {systems.~I}},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {30--37},
     publisher = {mathdoc},
     number = {12},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1976_12_a3/}
}