@article{PismaZhETF.60.673,
    title = {Pionium in decays of elementary particles},
    author = {Silagadze, Z. K.},
    journal = {Письма в ЖЭТФ},
    volume = {60},
    issue = {10},
    pages = {673},
    year = {1994},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_20420.shtml},
}