@article{JETPL.103.309, title = {}, author = {Chirkin, A. S.}, journal = {JETP Lett.}, volume = {103}, issue = {4}, pages = {282}, year = {2016}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X16040135}, note = {[Pisma v ZhETF 103, 309 (2016)]} }