1. Calvin, M.: BioSci. 29, 533 (1979) (and references cited therein)
2. Coffey, S.G., Halloran, G.M.: Search 10, 423 (1979); Hinman, C.W., et al.: Proc. Am. Solar Energy Soc. (in press); Bassham, J.A., in: Biochemical and Photosynthetic Aspects of Energy Production, p. 147. New York: Academic Press 1980; Hall, D.O.: Renewable Resources ? Hydrocarbon Fuels, in: Outlook in Agriculture (to be published June 1980)
3. Gold, T., Sater, S.: Sci. Am. 242(6), 154 (1980)
4. Morris, S.C., et al.: Science 206, 654 (1979)
5. Broecker, W.S., et al.: ibid. 206, 409 (1979)