1. Gerard, R. W., Scientific Monthly 50:349 (1940).
2. Bartlett, F. H., Sigmund Freud: 80 (1938).
3. COGHILL, G.E., The neuro-embryologic study of behavior principles, perspective and aim, SCIENCE 78: 131 (1933).
4. Collier, H., An Interpretation of Biology: CH5 (1938).
5. COMMONER, B, Structural relations in cell respiration, QUARTERLY REVIEW OF BIOLOGY 17: 46 (1942).