@article{PismaZhETF.37.85,
    title = {Generation of second harmonic of light in crystals with resonant impurities},
    author = {Zel'dovich, B. Ya. and Kuz'michev, S. D.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {37},
    issue = {2},
    pages = {85},
    year = {1983},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_22730.shtml},
}