1. Department of Chemistry, University of Buea, P.O. Box 63, Buea, SWR, Cameroon
2. Department of Chemistry, Higher Teachers Training College, University of Bamenda, Bambili, NWR, Cameroon
3. Department of Inorganic Chemistry, Coordination Chemistry Laboratory, University of Yaounde I, P.O. Box 812, Yaoundé, Cameroon
4. Department of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
5. Department of Pure and Applied Chemistry, University of Calabar, PMB 1115, Calabar, CRS, Nigeria