@article{PismaZhETF.45.61,
    title = {Do absolutely closed universes exist?},
    author = {Markov, M. A.},
    journal = {Письма в ЖЭТФ},
    volume = {45},
    issue = {2},
    pages = {61},
    year = {1987},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_18673.shtml},
}