@article{PismaZhETF.11.11,
    title = {Parametric Luminescence and Light Scattering by Polaritons},
    author = {Klyshko, D. N. and Penin, A. N. and Polkovnikov, B. F.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {11},
    issue = {1},
    pages = {11},
    year = {1970},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_26042.shtml},
}