@article{JETPL.98.251, title = {}, author = {, and Van?kov, A. B. and , and Kukushkin, I. V. and , and , and , and , and , and , }, journal = {JETP Lett.}, volume = {98}, issue = {4}, pages = {223}, year = {2013}, doi = {}, url = {http://jetpletters.ru/ps/0/article_30399.shtml}, note = {[Pisma v ZhETF 98, 251 (2013)]} }