1. AHENKORAH, Y., and AKROFI, G. S. (1972). Amelonado shade and fertilizer experiment. Rep. Cocoa Res. Inst. Ghana for 1968169.
2. JENNY, H. (1933). Soil fertility losses under Missouri conditions.Bull. Mo agric. Exp. Stn, No. 324.
3. MARCHANT, H. (1969). Chemical control of cocoa capsids: alternatives to lindane.Rep. 3rd int. Cocoa Res. Conf., Accra, Ghana, 173–85.
4. VERNON, A. J. (1966). Design and analysis of the Amelonado shade and manurial experi-ment, Kl.Rep. Cocoa Res. Inst. Ghana for 1963165, 104.