@article{PismaZhETF.83.3,
    title = { Composite dark matter from 4-th generation},
    author = {Khlopov, M. Yu.},
    journal = {Письма в ЖЭТФ},
    volume = {83},
    issue = {1},
    pages = {3},
    year = {2006},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_16033.shtml},
}