@article{JETPL.106.173, title = {}, author = {, and , and , and Zotov, A.}, journal = {JETP Lett.}, volume = {106}, issue = {3}, pages = {179}, year = {2017}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X17150097}, note = {[Pisma v ZhETF 106, 173 (2017)]} }