1. Genetics of duodenal and gastric ulcer;Cowan;Clin Gastroenterol,1973
2. The separarate inheritance of gastric and duodenal ulcers;Doll;Ann Eugenics,1951
3. Multiple endocrine adenomatosis;Rimoin,1971
4. Studies in duodenal ulcer, the clinical evidence for the existence of two populations;Lam;Q J Med,1975
5. Gastric and duodenal ulcer;McConnel,1966