1. Essay in the Theory of Risk Bearing;Arrow,1971
2. Environmental preservation, uncertainty and irreversibility;Arrow;Quarterly Journal of Economics,1974
3. Les migrations au Nord Cameroun;Beauvilain;Revue de Géographie du Cameroun,1980
4. The Conditions of Agricultural Growth;Boserup,1965
5. Magoumaz: Etude d'un Terroir de Montagne en Pays Mafa;Boulet,1971