1. Department of Mathematics, Air University, Islamabad, Pakistan
2. School of Mathematics and Statistics, Central South University, Changsha, PR China
3. Department of Mathematics, Capital University of Science and Technology (CUST), Islamabad, Pakistan
4. Department of Mathematics, Faculty of Science, New Valley University, Al-Wadi Al-Gadid, Egypt
5. Finance and Insurance Department, College of Business Administration, Northern Border University, Arar, Saudi Arabia