@article{JETPL.106.104, title = {}, author = {Pekh, P. L. and Ratnikov, P. V. and , }, journal = {JETP Lett.}, volume = {106}, issue = {2}, pages = {116}, year = {2017}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X17140090}, note = {[Pisma v ZhETF 106, 104 (2017)]} }