@article{JETPL.104.216,
    title = {},
    author = {,  and ,  and Tolokonnikov, S. V.},
    journal = {JETP Lett.},
    volume = {104},
    issue = {4},
    pages = {218},
    year = {2016},
    doi = {},
    url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X16160025},
    note = {[Pisma v ZhETF 104, 216 (2016)]}
}