@article{JETPL.98.459,
    title = {},
    author = {Val?kov, V. V. and Aksenov, S. V. and , },
    journal = {JETP Lett.},
    volume = {98},
    issue = {7},
    pages = {403},
    year = {2013},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_30452.shtml},
    note = {[Pisma v ZhETF 98, 459 (2013)]}
}