@article{JETPL.108.638,
    title = {},
    author = {Ruban, V. P.},
    journal = {JETP Lett.},
    volume = {108},
    issue = {9},
    pages = {605},
    year = {2018},
    doi = {},
    url = {http://jetpletters.ru/ps/dx/10.1134/S0370274X18210075},
    note = {[Pisma v ZhETF 108, 638 (2018)]}
}