1. Department of Mathematics, University of Agriculture, P.M.B. 2373, Makurdi, Nigeria
2. Department of Computer Science, University of Agriculture, P.M.B. 2373, Makurdi, Nigeria
3. Department of Mathematics, Quaid-i-Azam University, Islamabad, Pakistan
4. Department of Mathematics, Faculty of Arts and Sciences, Yildiz Technical University, Esenler 34220, Istanbul, Turkey
5. Department of Mathematics, Tri-Chandra Multiple Campus, Tribhuvan University, Kathmandu, Nepal