@article{DAN_1962_145_1_a3,
     author = {B. R. Vainberg},
     title = {Asymptotic representation of the fundamental solutions of hypo-elliptic equations and the problem},
     journal = {Doklady Akademii Nauk},
     pages = {21--23},
     year = {1962},
     volume = {145},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1962_145_1_a3/}
}