@article{JETPL.93.221, title = {}, author = {, and , and Kupriyanov, M. Yu. and , }, journal = {JETP Lett.}, volume = {93}, issue = {4}, pages = {203}, year = {2011}, doi = {}, url = {http://jetpletters.ru/ps/0/article_29160.shtml}, note = {[Pisma v ZhETF 93, 221 (2011)]} }