@article{JETPL.95.638,
    title = {},
    author = {,  and ,  and ,  and , },
    journal = {JETP Lett.},
    volume = {95},
    issue = {11},
    pages = {560},
    year = {2012},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_29749.shtml},
    note = {[Pisma v ZhETF 95, 638 (2012)]}
}