@article{JETPL.103.568, title = {}, author = {Kuzmin, V. L.}, journal = {JETP Lett.}, volume = {103}, issue = {8}, pages = {504}, year = {2016}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X16080026}, note = {[Pisma v ZhETF 103, 568 (2016)]} }