@article{JETPL.95.323, title = {}, author = {Chuev, M. A.}, journal = {JETP Lett.}, volume = {95}, issue = {6}, pages = {295}, year = {2012}, doi = {}, url = {http://jetpletters.ru/ps/0/article_29663.shtml}, note = {[Pisma v ZhETF 95, 323 (2012)]} }