1. School of Mathematical Sciences, C.K. Tedam University of Technology and Applied Sciences, P.O. Box 24, Navrongo, UER, Ghana
2. School of Engineering, University for Development Studies, Nyankpala Campus, P.O. Box 1882, Tamale, Ghana
3. Faculty of Military Science, Stellenbosch University, Private Bag X2, Saldanha 7395, South Africa