@article{JETPL.111.34,
    title = {},
    author = {, },
    journal = {JETP Lett.},
    volume = {111},
    issue = {1},
    pages = {41},
    year = {2020},
    doi = {},
    url = {http://jetpletters.ru/ps/dx/10.31857/S0370274X20010075},
    note = {[Pisma v ZhETF 111, 34 (2020)]}
}