@article{PismaZhETF.29.589,
    title = {$NH_3$ laser pumped by two $CO_2$ lasers},
    author = {Bobrovskii, A. N. and Vedenov, A. A. and Kozhevnikov, A. V. and Sobolenko, D. N.},
    journal = {Письма в ЖЭТФ},
    volume = {29},
    issue = {9},
    pages = {589},
    year = {1979},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_22155.shtml},
}