@article{PismaZhETF.20.264,
    title = {Nonlinear optical effects of fourth order in the field in a lithium formiate crystal},
    author = {Akhmanov, S. A. and Dubovik, A. N. and Saltiel, S. M. and Tomov, I. V. and Tunkin, V. G.},
    journal = {Письма в ЖЭТФ},
    volume = {20},
    issue = {4},
    pages = {264},
    year = {1974},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_27246.shtml},
}