1. Mulliken, R. S., J. Amer. Chem. Soc., 72, 600 (1950); J. Chim. Phys., France, 61, 20 (1964). Ferguson, E. E., J. Chim. Phys., France, 61, 257 (1964). Hassel, O., and Rømming, Chr., Quart. Revs., 16, 1 (1962). Cornil, P., Duchesne, J., Read, M., and Cahay, R., Bull. Acad. Roy. Sci. Belgium, 50, 235 (1964). See also Briegleb, G., Elektronen-Donator-Acceptor-Komplexe (Springer Verlag, Berlin, 1961).
2. Szent-Györgyi, A., Introduction to a Submolecular Biology, (Academic Press, London, 1960).
3. Szent-Györgyi, A., Isenberg, I., and Baird, S. L., Proc. U.S. Nat. Acad. Sci., 46, 1444 (1960).
4. See Pullman, B., J. Cell. and Comp. Physiol., supp. 1 64, 91 (1964).
5. Pullman, B., C.R. Acad. Sci., Paris, 259, 3101 (1964).