1. Enrich, W. E., Prog. Surgery, 1, 1 (1961).
2. Nossal, G. J. V., and Haekelae, O., Lab. Invest., 10, 1094 (1961).
3. Rebuck, J. W., and LoGrippo, G. A., Lab. Invest., 10, 1068 (1961).
4. Bernhard, W., and Granboulan, N., Ciba Symp. Cellular Aspects of Immunity, edit. by Wolstenholme, G. E. W., and O'Connor, C. M., 92 (Little, Brown and Co., Boston, 1960).
5. Thiery, J. P., ibid., 59.