1. Baker, K. F. and Cook, R. J. 1974 W. H. Freeman and Company. San Francisco.
2. Domros, M. 1974 The agroclimate of Ceylon. Franz Steiner Verlag GMBH, Wiesbaden.
3. Griffin, D. M. and Nair, N. G. 1968 J. Exp. Bot.19, 812–816.
4. Hansen, J. D. and Curl, E. A. 1959 Phytopathology49, 317–318.
5. Price, R. D. et al. 1971 Proc. Aust. conf. Soil Biol.1971, 50–51.