@article{PismaZhETF.17.442,
    title = {Sum Rules  in  Electron  Scattering by Nuclei},
    author = {Efros, V. D.},
    journal = {Письма в ЖЭТФ},
    volume = {17},
    issue = {8},
    pages = {442},
    year = {1973},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_23590.shtml},
}