1. Bock, F., and Mund, R., J. Invest. Derm., 26, 479 (1956).
2. Bock, F., and Mund, R., Cancer Res., 18, 887 (1958).
3. Healey, P., Mawdesley-Thomas, L. E., and Barry, D. H., Proc. Tenth Intern. Cancer Cong. (1970) (in the press).
4. Mawdesley-Thomas, L. E., and Healey, P., New Sci., February 6, 286 (1969).
5. Mawdesley-Thomas, L. E., and Healey, P., Science, 163, 1200 (1969).