@article{JETPL.104.763, title = {}, author = {, and , and , and Tolokonnikov, S. V.}, journal = {JETP Lett.}, volume = {104}, issue = {11}, pages = {743}, year = {2016}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X16230016}, note = {[Pisma v ZhETF 104, 763 (2016)]} }