@article{JETPL.97.742, title = {}, author = {, and Surovtsev, E. V.}, journal = {JETP Lett.}, volume = {97}, issue = {11}, pages = {644}, year = {2013}, doi = {}, url = {http://jetpletters.ru/ps/0/article_30318.shtml}, note = {[Pisma v ZhETF 97, 742 (2013)]} }