[Luo, Hua-Mei] Southwest Jiaotong Univ, Sch Math, Chengdu 610031, Sichuan, Peoples R China.
[Lin, Wenbin] Southwest Jiaotong Univ, Sch Phys Sci & Technol, Chengdu 610031, Sichuan, Peoples R China.
[Lin, Wenbin] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.
[Huang, Qing-Guo; Chen, Zu-Cheng] Chinese Acad Sci, Inst Theoret Phys, CAS Key Lab Theoret Phys, Beijing 100190, Peoples R China.
[Huang, Qing-Guo; Chen, Zu-Cheng] Univ Chinese Acad Sci, Sch Phys Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China.