1. v. Frisch, K. Experientia 6, 210–211 (1950).
2. Kramer, G. Naturwissenschaften 37, 377–378 (1950).
3. Kramer, G. & v. Saint-Paul, U. Naturwissenschaften 37, 526–527 (1950).
4. Chovnick, A. (ed.) Biological Clocks (The Biological Laboratory, Cold Spring Harbor, New York, 1960).
5. v. Frisch, K. The Dance Language and the Orientation of Bees (Harvard University Press, Massachusetts, 1967).