@article{PismaZhETF.54.189,
    title = {Topological phases for a system of three mixed Dirac neutrinos in a medium of varying density},
    author = {Naumov, V. A.},
    journal = {Письма в ЖЭТФ},
    volume = {54},
    issue = {4},
    pages = {189},
    year = {1991},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_18116.shtml},
}