@article{DE_1988_24_10_a25,
     author = {I. V. Ponomarev and A. M. Khapaev},
     title = {On the variational method for solving the problem of electron-wave interaction},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1828--1831},
     publisher = {mathdoc},
     volume = {24},
     number = {10},
     year = {1988},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1988_24_10_a25/}
}