@article{JETPL.106.199, title = {}, author = {, and Nikolaev, N. N. and , and , and , and , }, journal = {JETP Lett.}, volume = {106}, issue = {4}, pages = {213}, year = {2017}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X17160020}, note = {[Pisma v ZhETF 106, 199 (2017)]} }