1. Muller, H. J. in 4th International Congress of Plant Science 917–918 (ed. Duggar, B. M.) 917–918 (Bantha Publishing, Menasha, 1929)
2. Podolsky, S. The role of the virus in origin-of-life theorizing. J. Hist. Biol. 29, 79–126 (1996).
3. Simon, C. E. (ed.) The Filterable Viruses (Reinhold, New York, 1928).
4. Haldane, J. B. S. The origin of life. Rationalist Ann. 3–10 (1929).
5. Beutner, R. Life's Beginning on the Earth (Williams and Wilkins, Baltimore, 1938).