@article{PismaZhETF.60.85,
    title = {Description of optical echo without the given-field approximation},
    author = {Khadzhi, P. I.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {60},
    issue = {2},
    pages = {85},
    year = {1994},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_19985.shtml},
}