@article{JETPL.97.404, title = {}, author = {, and , and , and , and Dvoretsky, S. A.}, journal = {JETP Lett.}, volume = {97}, issue = {6}, pages = {358}, year = {2013}, doi = {}, url = {http://jetpletters.ru/ps/0/article_30242.shtml}, note = {[Pisma v ZhETF 97, 404 (2013)]} }