@article{PismaZhETF.28.198,
    title = {Nonlinearity of single-photon absorption in a superconductor near the threshold},
    author = {Bratus', E. N. and Shumeiko, V. S},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {28},
    issue = {4},
    pages = {198},
    year = {1978},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_24120.shtml},
}