@article{JETPL.95.638, title = {}, author = {, and , and , and Fedyanin, A. A.}, journal = {JETP Lett.}, volume = {95}, issue = {11}, pages = {560}, year = {2012}, doi = {}, url = {http://jetpletters.ru/ps/0/article_29749.shtml}, note = {[Pisma v ZhETF 95, 638 (2012)]} }