1. Department of Mathematics, AIR University, Sector E-9 Islamabad, Pakistan
2. Department of Mathematics and Statistics, College of Science, Taif University, Taif 21944, Saudi Arabia
3. Mathematics Department, Al-Qunfudah University College, Umm Al-Qura University, Mecca, Saudi Arabia
4. Department of Mathematics, Division of Science and Technology, University of Education, Lahore 54770, Pakistan