@article{PismaZhETF.24.64,
    title = {Discrete echo in lithium niobate},
    author = {Smolyakov, B. P. and Shtyrkov, E. I.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {24},
    issue = {2},
    pages = {64},
    year = {1976},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_27655.shtml},
}