1. Department of Geology, Higher Teacher Training College, The University of Bamenda, P.O. Box 39, Bambili, Cameroon
2. Department of Soil Science, University of Dschang, P.O. Box 222, Dschang, Cameroon
3. Department of Mining and Mineral Engineering, National Higher Polytechnic Institute, University of Bamenda, P.O. Box 39, Bambili, Cameroon
4. Department of Earth Sciences, University of Ngaoundéré, P.O. Box 454, Ngaoundéré, Cameroon