@article{JETPL.103.189, title = {}, author = {, and , and Gritsenko, V. A.}, journal = {JETP Lett.}, volume = {103}, issue = {3}, pages = {171}, year = {2016}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X16030061}, note = {[Pisma v ZhETF 103, 189 (2016)]} }