@article{PismaZhETF.74.499,
    title = {BL Lacertae are probable sources of the observed ultra-high energy cosmic rays},
    author = {Tinyakov, P. G. and Tkachev, I. I.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {74},
    issue = {9},
    pages = {499},
    year = {2001},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_9621.shtml},
}