@article{DE_1999_35_1_a15,
     author = {S. F. Nikolaev and E. L. Tonkov},
     title = {The structure of the controllability set of a linear subcritical system},
     journal = {Differencialʹnye uravneni\^a},
     pages = {107--115},
     publisher = {mathdoc},
     volume = {35},
     number = {1},
     year = {1999},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1999_35_1_a15/}
}