Affiliation: | GAN Shixin1,CHEN Pingyan2,QIU Dehua3 1.School of Mathematics and Statistics,Wuhan University,Wuhan 430072,Hubei,China,2.Department of Mathematics,Jinan University,Guangzhou 510630,Guangdong,3.Department of Mathematics and Computer Science,Guangdong Business College,Guangzhou 510320 |