@article{JETPL.104.629, title = {}, author = {Dyugaev, A. M. and , }, journal = {JETP Lett.}, volume = {104}, issue = {9}, pages = {639}, year = {2016}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X16210025}, note = {[Pisma v ZhETF 104, 629 (2016)]} }