1. D. Hess, in: Plant Cell, Tissue, and Organ Culture, p. 506. Ed. J. Reinert and Y. P. S. Bajaj. Springer, Berlin-Heidelberg-New York 1977.
2. M. Suzuki and I. Takebe, Z. PflPhysiol.78, 421 (1976).
3. B. Liebke and D. Hess, Biochem. Physiol. Pflanzen, in press (1977).
4. D. Hess, in: Microbial and Plant Protoplasts, p. 125. Ed. J. F. Peberdy, A. H. Rose, H. J. Rogers and E. C. Cocking. Academic Press, London 1976.
5. B. Liebke, W. Blaschek and D. Hess, Z. PflPhysiol., in press (1977).