@article{PismaZhETF.49.597,
    title = {Characteristic features of the low-temperature luminescence of $YBa_2Cu_3O_{7-x}$},
    author = {Gaisin, V. A. and Kulinkin, B. S. and Novikov, B. V.},
    journal = {Письма в ЖЭТФ},
    volume = {49},
    issue = {11},
    pages = {597},
    year = {1989},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_16995.shtml},
}