1. Acland J C 1975 East African Crops. pp 59–89. Longmans, London.
2. Allen S, Grimshaw M, Partinson J and Quarmby J C (Eds.) 1974 Chemical Analysis of Ecological Materials. Blackwell Scientific Publications, London.
3. Bock K R 1956 Investigations on coffee berry disease; laboratory studies. E. Afr. Agric. J. 22, 97–103.
4. Cordero A, Ramirez G F 1979 Copper accumulation in the soils of the South Pacific area of Costa Rica and its detrimental effects in agriculture. Agron. Costarr. 3, 63–78.
5. Dickinson N M, Lepp N W and Ormand K L (in press) Copper contamination of a 68 year old coffee (Coffea arabica L) plantation. Environ. Pollut. Ser. A.