@article{JETPL.98.389, title = {}, author = {, and Shpatakovskaya, G. V.}, journal = {JETP Lett.}, volume = {98}, issue = {6}, pages = {348}, year = {2013}, doi = {}, url = {http://jetpletters.ru/ps/0/article_30425.shtml}, note = {[Pisma v ZhETF 98, 389 (2013)]} }