@article{PismaZhETF.13.351,
    title = {Direct Proof of the Existence of an Excited Negative $\epsilon^-$ Ion and the Determination of the Binding Energy of the Electron In It},
    author = {Oparin, V. A. and II'in, R. N. and Serenkov, I. T. and Solov'ev, E. S. and Fedorenko, N. V.},
    journal = {Письма в ЖЭТФ},
    volume = {13},
    issue = {7},
    pages = {351},
    year = {1971},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_24253.shtml},
}