1. Department of Mathematics, Himwant Kavi Chandra Kunwar Bartwal Govt. P.G. College, Nagnath Pokhari, Uttarakhand, India
2. Department of Mathematics and Statistics, International Islamic University, H-10, Islamabad 44000, Pakistan
3. Department of Mathematics, HNB Garhwal University, Uttarakhand, India
4. Department of Mathematics Education, Akenten Appiah-Menka University of Skills Training and Entrepreneurial Development, Kumasi 00233, Ghana