@article{PismaZhETF.49.147,
    title = {Ion-charge scaling law for electron and optical spectra},
    author = {Protasov, Yu. S. and Chuvashev, S. N.},
    journal = {Письма в ЖЭТФ},
    volume = {49},
    issue = {3},
    pages = {147},
    year = {1989},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_16861.shtml},
}