@article{PismaZhETF.39.304,
    title = {Unusual splitting of the spectrum of collective modes in superfluid $^3He-B$},
    author = {Volovik, G. E.},
    journal = {Письма в ЖЭТФ},
    volume = {39},
    issue = {7},
    pages = {304},
    year = {1984},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_19620.shtml},
}