1. Faculty of Science, University of Yaounde 1, P.O. Box 812, Yaounde, Cameroon
2. Department of Renewable Energy, Higher Technical Teachers’ Training College (HTTTC), University of Buea, P.O. Box 249, Cameroon
3. National Institute of Cartography (NIC), P.O. Box 157, Yaounde, Cameroon
4. Faculty of Industrial Engineering, University of Douala, P.O. Box 2701, Cameroon