@article{DAN_1967_176_1_a14,
     author = {V. N. Lugovoi},
     title = {Propagation of wave beams in non-linear media},
     journal = {Doklady Akademii Nauk},
     pages = {58--61},
     publisher = {mathdoc},
     volume = {176},
     number = {1},
     year = {1967},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1967_176_1_a14/}
}