1. Bucher, N. L. R., Intern. Rev. Cytol., 15, 245 (1963).
2. Leong, G. F., Grisham, J. W., Hole, B. V., and Albright, M. L., Cancer Res., 24, 1496 (1964).
3. Mann, F. C., J. Mt. Sinai Hosp., 11, 65 (1944).
4. Higgins, G. M., Mann, F. C., and Priestley, J. T., Arch. Path. (Lab. Med.), 14, 491 (1932).
5. Sigel, B., Arch. Surg. (Chicago), 87, 788 (1963).