@article{JETPL.106.689,
    title = {},
    author = {,  and ,  and , },
    journal = {JETP Lett.},
    volume = {106},
    issue = {11},
    pages = {720},
    year = {2017},
    doi = {},
    url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X17230060},
    note = {[Pisma v ZhETF 106, 689 (2017)]}
}