@article{PismaZhETF.53.188,
    title = {Time-varying diffraction effects in the propagation of an electromagnetic pulse in vacuum},
    author = {Belenov, E. M. and Nazarkin, A. V.},
    journal = {Письма в ЖЭТФ},
    volume = {53},
    issue = {4},
    pages = {188},
    year = {1991},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_17388.shtml},
}