@article{ZVMMF_1998_38_12_a10,
     author = {V. A. Trofimov},
     title = {An invariant of femtosecond-pulse propagation in a nonlinear absorptive medium},
     journal = {\v{Z}urnal vy\v{c}islitelʹnoj matematiki i matemati\v{c}eskoj fiziki},
     pages = {2055--2059},
     publisher = {mathdoc},
     volume = {38},
     number = {12},
     year = {1998},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZVMMF_1998_38_12_a10/}
}