1. Nichol, J. C., and Deutsch, H. F., J. Amer. Clin. Soc., 70, 80 (1948).
2. Richards, C. B., and Marrack, J. R., in The Protides of Biological Fluids, edit. by Peeters, E., 142 (1964).
3. Weiner, L. M., Macko, I., Poulik, E., and Goodman, M., J. Immunol., 83, 228 (1964).
4. Edelman, G. M., and Poulik, M. D., J. Exp. Med., 113, 861 (1961).
5. Franklin, E. C., Proc. Soc. Exp. Biol. and Med., 109, 338 (1962).