@article{DE_1991_27_10_a4,
     author = {A. G. Ivanov and E. L. Tonkov},
     title = {On the controllability set of a linear almost periodic system},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1692--1699},
     publisher = {mathdoc},
     volume = {27},
     number = {10},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1991_27_10_a4/}
}