@article{DAN_1967_172_3_a4,
     author = {D. M. Grobman},
     title = {The neighborhood of a singular point of a system of differential equations with small non-linearities},
     journal = {Doklady Akademii Nauk},
     pages = {524--526},
     publisher = {mathdoc},
     volume = {172},
     number = {3},
     year = {1967},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1967_172_3_a4/}
}