@article{PismaZhETF.48.13,
    title = {Cancellation of non-Abelian anomalies; the electric charge of quarks},
    author = {Koval'chuk, V. A.},
    journal = {Письма в ЖЭТФ},
    volume = {48},
    issue = {1},
    pages = {13},
    year = {1988},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_16625.shtml},
}