1. Chemical Manufacturers;Cancer Rev.,;London. Berenblum; Papilloma of the Bladder in the Chemical Industry,1953
2. Case, R. A. M. (1953a). Brit. J. prev. soc. Med., 7, 14.
3. , (1953b). British Journal of Industrial Medicine, 10, 114.
4. ,, Hosker, M. E., McDonald, D. B., and Pearson, J. T. (1954). Ibid., 11, 75.
5. Statistical Tables for Biological, Agricultural and Medical Research, Table VIII;Fisher, R.A.; Yates, F.,1948