1. Andersen, R. and M. J. Kasperbauer. 1973. Chemical composition of tobacco leaves altered by near-ultraviolet and intensity of visible light. Plant Physiol. 51: 723–726.
2. Arnon, D. I. 1949. Copper enzymes in isolated chloroplasts, polyphenol-oxidase in Beta vulgaris. Plant Physiol. 24: l-15.
3. Basiouny, F. M., T. K. Van, and R. H. Biggs. 1978. Some morphological and biochemical characteristics of C3 and C4 plants irradiated with UV-B. Physiol. Plan 42: 29.
4. Bener, P. 1968. Spectral intensity of natural ultraviolet radiation and its dependence on various parameters. In: The Biologic Effects of Ultraviolet Radiation, F. Urbach [ed.] Pergamon Press Oxford. 351–358.
5. Bener, P. 1972. Approximate values intensity of natural ultraviolet radiation for different amounts of atmospheric ozone. European Research Office, US Army, London. Contrakt Number DAJA 37–68-C-1017. 4–59.