@article{PismaZhETF.13.261,
    title = {Production of $e^+e^-$ Pairs in an Alternating External Field},
    author = {Popov, V. S.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {13},
    issue = {5},
    pages = {261},
    year = {1971},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_24076.shtml},
}