@article{PismaZhETF.19.23,
    title = {Self-focusing of Langmuir Oscillations},
    author = {Litvak, A. G. and Fraiman, G. M. and Yunakovskii, A. D.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {19},
    issue = {1},
    pages = {23},
    year = {1974},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_26933.shtml},
}