1. Heath, J. C., Nature, 173, 822 (1954).
2. Heath, J. C., Brit. J. Cancer, 10, 668 (1956).
3. Heath, J. C., Brit. J. Cancer, 14, 478 (1960).
4. Webb, M., Dingle, J. T., Daniel, M. R., and Heath, J. C. (unpublished results).
5. Heath, J. C., Daniel, M. R., Dingle, J. T., and Webb, M., Brit. Emp. Cancer Camp., Thirty-eighth Ann. Rep., 373 (1960).