Institution: | 1.Department of Mathematics,
University of Science and Technology of China, Hefei 230026, China;Department of Mathematics,
Xuzhou Normal University, Xuzhou 221116, China; 2.Mathematics and
Information Engineering Department, Anyang Normal University, Anyang
455000, China;Department of Mathematics,
Xuzhou Normal University, Xuzhou 221116, China; 3.Department of Mathematics,
Xuzhou Normal University, Xuzhou 221116, China; |