1. Department of Architecture and Urban Planning, National Advanced School of Public Work, P.O. Box 510, Yaoundé, Cameroon.
2. Department of Textile and Leather Engineering, National Advanced School of Engineering, University of Maroua, P.O. Box 46, Maroua, Cameroon.
3. Department of Chemistry, University of Bangui PO Box 908, Bangui, Central African Republic.
4. Department of Textiles, Institute of Industrial Systems and Textile Engineering, Polytechnic School of Ouagadougou (EPO), 18 BP234 Ouagadougou, Burkina Faso.