@article{PismaZhETF.27.527,
    title = {The $\mu \to e+\gamma$ decay and mixing of charged heavy leptons},
    author = {Koval'chuk, V. A. and Rekalo, A. P.},
    journal = {Письма в ЖЭТФ},
    volume = {27},
    issue = {9},
    pages = {527},
    year = {1978},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_23762.shtml},
}