@article{TMF_2011_166_1_a3,
     author = {A. G. Meshkov and V. V. Sokolov},
     title = {Hyperbolic equations with third-order symmetries},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {51--67},
     year = {2011},
     volume = {166},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_2011_166_1_a3/}
}