1. Department of Mathematics and Computer Science, Youjiang Medical University for Nationalities, Baise 533000, China
2. Department of Mathematics, Air University Multan Campus, Multan, Pakistan
3. Department of Computer Science and Mathematics, Lebanese American University, Beirut P.O. Box 13-5053, Lebanon
4. Department of Basic Sciences and Related Studies, Mehran University of Engineering & Technology, Jamshoro, Pakistan
5. Department of Mathematics, Near East University, Mersin, Turkey