1. Adams, M.H.: Bacteriophages, New York: Wiley (Interscience), 1959
2. Adolph, K.W., Haselkorn, R.: Isolation and characterization of a virus infecting the blue-green alga Nostoc muscorum. Virology 16, 200–208 (1971)
3. Allen, M.B., Arnon, D.I.: Studies on nitrogen-fixing blue-green algae. I. Growth and nitrogen fixation by Anabaena cylindrica Lemm. Plant Physiol 30, 366–372 (1955)
4. Crowe, A., Crowe, A.: Mathematics for biologists, London and New York: Academic Press 1969
5. Das, B., Singh, P.K.: Growth and nitrogen fixation of a mutant of the blue-green alga Anabaenopsis raciborskii defective in heterocyst differentiation. Beitr. Biol. Pflanzen 51, 325–334 (1975)