1. Bateman, A J. 1952. Self-incompatibility in angiosperms. I-Theory. Heredity, 6, 285–310.
2. Bennett, M C, and Cope, F W. 1959. Nuclear fusion and non-fusion in Theobroma cacao L. Nature, London, 183, 1540.
3. Cope, F W. 1939a. Some factors controlling the yield of young cacao II. 8th Ann Rep on Cacao Res (1938), Trinidad, 4–15.
4. Cope, F W. 1939b. Studies in the mechanism of self-incompatibility in cacao I. 8th Ann Rep on Cacao Res (1938), Trinidad, 20–21.
5. Cope, F W. 1940. Studies in the mechanism of self-incompatibility in cacao II. 9th Ann Rep on Cacao Res (1939), Trinidad, 19–23.