1. Aberg B 1958, Ruhland W (ed) Encycl PI Physiol 6: 479. Berlin; Springer Verlag.
2. Abraham PC 1969. Ph.D. Thesis, Botany Department, University School of Sciences, Gujarat University, Ahmedabad-380009, India.
3. Abraham PG, Dave IC, Pandya RB, Saxena OP 1968. Proc Nat Acad Sci Sec Biol. Abst. 98: 48.
4. Arnon DI 1955, Science 122: 9.
5. Arnon DI 1958, Chloroplast and Photosynthesis, Brookhaven Symp No, 11, p. 181.