@article{DE_1979_15_11_a6, author = {N. N. Petrov}, title = {Symmetric completely controllable control systems}, journal = {Differencialʹnye uravneni\^a}, pages = {1980--1986}, publisher = {mathdoc}, volume = {15}, number = {11}, year = {1979}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1979_15_11_a6/} }