1. Department of Mathematics, University of the Punjab, Lahore 54590, Pakistan
2. Department of Mathematics, Quaid-i-Azam University, Islamabad 44000, Pakistan
3. Department of Mathematics, Wenzhou University, Wenzhou, China
4. Department of Computer Science, College of Computers and Information Technology, Taif University, P. O. Box 11099, Taif 21944, Saudi Arabia
5. Basic Sciences Department, College of Science and Theoretical Studies, Saudi Electronic University, Jeddah-F, Saudi Arabia
6. Basic Sciences Department, College of Science and Theoretical Studies, Saudi Electronic University, Abha-M, Saudi Arabia