@article{PismaZhETF.17.431,
    title = {Effects   of  the  Optical   "Nutation"  Type   in  Multiple   Photon   Echo},
    author = {Zakharov, S. M. and Manykin, E. A.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {17},
    issue = {8},
    pages = {431},
    year = {1973},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_23587.shtml},
}