1. Department of Mathematics, Capital University of Science and Technology (CUST), Islamabad, Pakistan
2. Department of Mathematics, Faculty of Science, New Valley University, Al-Kharga, Egypt
3. Department of Mathematics, Faculty of Science, Northern Border University, Arar, Saudi Arabia
4. Department of Mathematics, Lahore College for Women University, Lahore, Pakistan
5. Department of Mathematics, School of Sciences, SR University, Warangal, India