by Wang, Di (迪王), Wan, Song-Ming (松明 万), Zhang, Qing-Li (庆礼 张), Sun, Dun-Lu (敦陆 孙), Gu, Gui-Xin (桂新 顾), Yin, Shao-Tang (绍唐 殷), Zhang, Guo-Chun (国春 张), You, Jing-Lin (静林 尤), Wang, Yuan-Yuan (媛媛 王)
Published in Chinese physics B (01.10.2011)