1. Laboratory of Materials, Local Material Promotion Authority MINRESI/MIPROMALO Cameroon, Yaoundé Cameroon
2. Department of Civil Engineering, National Advanced School of Engineering University of Yaoundé I Yaoundé Cameroon
3. Department of Minerals Engineering, School of Chemical Engineering and Mineral Industries (EGCIM) University of Ngaoundéré Ngaoundéré Cameroon
4. Laboratory of Applied Inorganic Chemistry, Faculty of Science University of Yaoundé I Yaoundé Cameroon