1. Department of Mathematics, Abdul Wali Khan University Mardan, Mardan 23200, Pakistan
2. Department of Mathematics, The University of Jordon, Amman 11942, Jordan
3. Department of Mathematics, Taibah University, Universities Road, P.O. Box 344, Medina 42353, Saudi Arabia
4. Department of Mathematics, College of Science, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia