@article{JETPL.106.569, title = {}, author = {Sadovnikov, S. I. and , and Gusev, A. I.}, journal = {JETP Lett.}, volume = {106}, issue = {9}, pages = {587}, year = {2017}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X1721007X}, note = {[Pisma v ZhETF 106, 569 (2017)]} }