@article{PismaZhETF.7.178,
    title = {Mass Difference of $K_S^0$ and $K_L^0$ Mesons, Mass of W Meson, and Sum Rules for Spectral Functions.},
    author = {Gedalin, E. V. and Kancheli, O. V. and Matinyan, S. G.},
    journal = {Письма в ЖЭТФ},
    volume = {7},
    issue = {5},
    pages = {178},
    year = {1968},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_25610.shtml},
}