1. Alberts, B., Bray, D., Lewis, J., Raff, M., Roberts, K., and Watson, J. D. (1994) Molecular Biology of the Cell (3rd Edition), Garland Publishing, Inc., New York.
2. Copelend, H. F. (1956) Classification of the Lower organisms, Pacific Book, Palo Alto, Calif.
3. Curtis, H. (1968) Biology, Worth, New York.
4. Horowitz, N. H. (1945) Proc. Natl. Acad. Science., USA 31, 153–157.
5. Jensen, T. E. (1994) In: J. Seckbach (ed.) Evolutionary Pathways and Enigmatic Algae: Cyanidium caldarium (Rhodophyta) and Related Cells, Kluwer Academic Publishers, Dordrecht, pp. 53–66.