@article{PismaZhETF.28.298,
    title = {Dispersion representation for the Lagrange function of an intense field},
    author = {Lebedev, S. L. and Ritus, V. I.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {28},
    issue = {5},
    pages = {298},
    year = {1978},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_24145.shtml},
}