@article{ZNSL_2012_401_a2,
     author = {M. F. Gamal'},
     title = {On control subspaces of minimal dimension},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {71--81},
     year = {2012},
     volume = {401},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2012_401_a2/}
}