@article{DAN_1979_248_2_a3,
     author = {A. M. Vinogradov},
     title = {The theory of higher infinitesimal symmetries of nonlinear partial differential equations},
     journal = {Doklady Akademii Nauk},
     pages = {274--278},
     publisher = {mathdoc},
     volume = {248},
     number = {2},
     year = {1979},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1979_248_2_a3/}
}