1. Department of Chemistry, Faculty of Science, University of Maroua, Maroua, Cameroon
2. Department of Refining and Petrochemistry, National Advanced School of Mines and Petroleum Industries, University of Maroua, Kaélé, Cameroon
3. Department of Life and Earth Sciences, Higher Teachers’ Training College, University of Maroua, Maroua, Cameroun
4. Department of Chemistry, Faculty of Science, University of Ngaoundéré, Ngaoundéré, Cameroon
5. Department of General, Organic and Biomedical Chemistry, Faculty of Medicine and Pharmacy, University of Mons, NMR and Molecular Imaging Laboratory, Mons, Belgium
6. Independent Researcher, Italy