1. Bradley, D. F., Lifson, S., and Honig, B., Electronic Aspects of Biochemistry (edit. by Pullman, B.), 77 (Academic Press, 1964).
2. Nash, H. A., and Bradley, D. F., Biopolymers, 3, 261 (1965).
3. Nash, H. A., and Bradley, D. F., J. Chem. Phys., 45, 1380 (1966).
4. Bradley, D. F., and Nash, H. A., Molecular Associations in Biology (edit. by Pullman, B.), 137 (Academic Press, 1968).
5. Del Re, G., J. Chem. Soc., 4031 (1968).