@article{PismaZhETF.30.22,
    title = {Ground state energy shift in the proton-antiproton atom},
    author = {Kerbikov, B. O.},
    journal = {Письма в ЖЭТФ},
    volume = {30},
    issue = {1},
    pages = {22},
    year = {1979},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_20572.shtml},
}