@article{JETPL.104.3, title = {}, author = {Gus?kov, S. Yu. and , }, journal = {JETP Lett.}, volume = {104}, issue = {1}, pages = {1}, year = {2016}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X16130014}, note = {[Pisma v ZhETF 104, 3 (2016)]} }