1. Ashford, D., Neuberger, A.: 4-Hydroxyproline in plant glycoproteins. Where does it come from and what is it doing there? - Trends biochem. Sci.5: 245–248, 1980.
2. Britikov, E. A., Musatova, N. A., Vladimirtseva, S. V., Protsenko, M. A.: Proline in the reproductive system of plants. - In:Linskens, H. F. (ed.): Pollen Physiology and Fertilization. Pp. 77–85. North-Holland Publ., Amsterdam 1964.
3. Dvořák, M.: On the phenolic compounds inCucurbita pepo L. plants and their relation to nutrition with calcium.- Acta Univ. Carolinae biol.1971: 99–114, 1973.
4. Dvořák, M., Černohorská, J.: Comparison of effects of calcium deficiency and IAA on the pumpkin plant (Cucurbita pepo L.) - Biol. Plant.14: 28–38, 1972.
5. Fukasawa, H.: Biochemical mechanism of pollen abortion and other alterations in cytoplasmic male sterile wheat. - In: Proc. Second Wheat Genet. Symp., Japan Seiken Ziho13: 107 to 111, 1962.