@article{JETPL.96.804,
    title = {},
    author = {Tkachenko, O. A. and Tkachenko, V. A.},
    journal = {JETP Lett.},
    volume = {96},
    issue = {11},
    pages = {719},
    year = {2012},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_30096.shtml},
    note = {[Pisma v ZhETF 96, 804 (2012)]}
}