@article{JETPL.96.528,
    title = {},
    author = {,  and Chulkov, E. V.},
    journal = {JETP Lett.},
    volume = {96},
    issue = {7},
    pages = {480},
    year = {2012},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_29980.shtml},
    note = {[Pisma v ZhETF 96, 528 (2012)]}
}