@article{JETPL.107.223, title = {}, author = {, and , and , and , and , and , and , and , and , and , and , and Khartchev, N. K.}, journal = {JETP Lett.}, volume = {107}, issue = {4}, pages = {219}, year = {2018}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X18040033}, note = {[Pisma v ZhETF 107, 223 (2018)]} }