@article{DAN_1966_166_3_a9,
     author = {A. I. Perov},
     title = {Investigation in the neighborhood of a singular point of a multi-dimensional differential equation in the analytic case},
     journal = {Doklady Akademii Nauk},
     pages = {544--547},
     publisher = {mathdoc},
     volume = {166},
     number = {3},
     year = {1966},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1966_166_3_a9/}
}