@article{JETPL.96.607, title = {}, author = {, and Leonidov, A. V.}, journal = {JETP Lett.}, volume = {96}, issue = {8}, pages = {554}, year = {2012}, doi = {}, url = {http://jetpletters.ru/ps/0/article_30011.shtml}, note = {[Pisma v ZhETF 96, 607 (2012)]} }