@article{JETPL.108.236, title = {}, author = {, and , and Alshits, V. I. and , and , }, journal = {JETP Lett.}, volume = {108}, issue = {4}, pages = {231}, year = {2018}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.1134/S0370274X18160038}, note = {[Pisma v ZhETF 108, 236 (2018)]} }