@article{PismaZhETF.13.43,
    title = {Observation of $\gamma$ Quanta with Energy larger than 100 MeV from the Radio Source 3Cl20},
    author = {Volobuev, S. A and Gal'per, A. M. and Kirillov-Ugryumov, V. G. and Luchkov, B. I. and Ozerov, Yu. V.},
    journal = {Письма в ЖЭТФ},
    volume = {13},
    issue = {1},
    pages = {43},
    year = {1971},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_23968.shtml},
}