a Ghent University, Faculty of Bioscience Engineering, Department of Agricultural Economics, Coupure Links 653, 9000 Ghent, Belgium b Ghent University, Faculty of Bioscience Engineering, Laboratory of Tropical and Subtropical Agronomy and Ethnobotany, Coupure Links 653, 9000 Ghent, Belgium c World Agroforestry Centre, West and Central African Region (ICRAF-WCA), PO Box 16317 Yaounde, Cameroon d...
