1. Department of Mathematics, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
2. Department of Mathematics, Faculty of Natural Sciences, HITEC University, Taxila 47080, Pakistan
3. Department of Mathematics, College of Science, King Khalid University, Abha 61413, Saudi Arabia
4. Department of Mathematics, Gomal University, Dera Ismail Khan 29050, Pakistan