1. Department of Mathematics, University of Peshawar, Peshawar, 25120 Khyber Pakhtunkhwa, Pakistan
2. Department of Mathematics, University of Swabi, Swabi, Khyber Pakhtunkhwa, Pakistan
3. Department of Mathematics Education, Akenten Appiah Menka University of Skills Training and Entrepreneurial Development, Kumasi, Ghana
4. Department of Mathematics, Abdul Wali Khan University, Mardan, 23200 Khyber Pakhtunkhwa, Pakistan