1. Batts, M., Jr. (1939). Arch. Surg. (Chicago), 39, 807.
2. Dolin, S., and Dewar, J. P. (1956). Amer. J. Path., 32, 83.
3. Favis, E. A., Kerman, H. D., and Schildecker, W. (1960). Amler. J. Med., 28, 323.
4. Gordon, J., and Walker, G. (1944). Arch. Path. (Chicago). 37, 222.
5. Greene, L. (1956). Med. Tms (N.Y.), C4, 1205.