@article{PismaZhETF.3.436,
    title = {Population Inversion in Adiabatic Expansion of a Gas Mixture},
    author = {Konyukhov, V. K. and Prokhorov, A. M.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {3},
    issue = {11},
    pages = {436},
    year = {1966},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_24792.shtml},
}