@article{PismaZhETF.25.240,
    title = {Observation of interference of direct and cascade processes in active spectroscopy of polaritons},
    author = {Polivanov, Yu. N. and Sukhodol'skii, A. T.},
    journal = {Письма в ЖЭТФ},
    volume = {25},
    issue = {5},
    pages = {240},
    year = {1977},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_21132.shtml},
}