1. Barron, M. E.: Simple nonspecific ulcer of the colon. Arch. Surg.17: 355, 1928.
2. Beaumont, W.: Experiments and Observations on the Gastric Juice and the Physiology of Digestion. Plattsburgh, New York, F. P. Allen, 1833. (Reproduction on occasion of 13th Intern. Physiologic Congress, Boston, 1929, p. 109.)
3. Bockus, H. L.: Personal communication to the authors.
4. Combes, C.: Simple ulcer of the intestine. Thesis, Toulouse, 1897.
5. Cruveilhier, J.: Rectum. Atlas d’anatomic et pathologie. 1830, p. 4.