@article{DAN_1988_303_4_a4,
     author = {Kh. G. Guseinov and V. N. Ushakov},
     title = {Strongly and weakly invariant sets with respect to a differential},
     journal = {Doklady Akademii Nauk},
     pages = {794--796},
     publisher = {mathdoc},
     volume = {303},
     number = {4},
     year = {1988},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1988_303_4_a4/}
}