1. W. J. P. Neish, Exper.14, 287 (1958);15, 20 (1959); Naturwissenschaften46, 175 (1959).
2. J. M. Vandenbelt, C. Pfeiffer, M. Kaiser, andM. Sibert, J. Pharmacol. exp. Therap.80, 31 (1944).
3. E. C. Miller andJ. A. Miller, Cancer Res.12, 547 (1952).
4. J. C. Arcos andM. Arcos, Biochim. biophys. Acta28, 9 (1958).
5. P.-G. Roy, T. S. Miya, andC. J. Carr, Proc. Soc. exp. Biol. Med.97, 284 (1958).