1. Progress report Familial inflammatory bowel disease—hereditary or environment?;Lewkonia;Gut,1960
2. Genetic aspects of inflammatory bowel disease;Kirsner;Clin Gastroenterol,1973
3. The epidemiology of inflammatory bowel disease;Mendeloff;Clin Gastroenterol,1980
4. Studies of family history among patients with inflammatory bowel disease;Farmer;Clin Gastroenterol,1980
5. Familial incidence of Crohn's disease in the Netherlands and a review of the literature;Weterman;Gastroenterology,1984