1. Department of Chemistry, Faculty of Science, The University of Maroua, Maroua, Cameroon
2. Department of Refining and Petrochemistry, National Advanced School of Mines and Petroleum Industries, The University of Maroua, Maroua, Cameroon
3. Department of Life and Earth Sciences, Higher Teachers’ Training College, The University of Maroua, Maroua, Cameroon
4. Department of Chemistry, Faculty of Science, University of Buea, Buea, Cameroon
5. International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan
6. Independent Researcher, Italy