@article{PismaZhETF.24.495,
    title = {Bound states of large number of magnons in a three-dimensional ferromagnet (magnons drops)},
    author = {Ivanov, B. A. and Kosevich, A. M.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {24},
    issue = {9},
    pages = {495},
    year = {1976},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_27757.shtml},
}