@article{TMF_2001_127_1_a4,
     author = {S. Ya. Startsev},
     title = {Hyperbolic {Equations} {Admitting} {Differential} {Substitutions}},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {63--74},
     publisher = {mathdoc},
     volume = {127},
     number = {1},
     year = {2001},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_2001_127_1_a4/}
}