1. Stanciu C, Bennett JR (1973) Gut 14:275–279
2. Lux G, Engel H, Rosh W (1981) Royal Society of Medicine International Congress and Symposium Series 36:29
3. Weihrauch TR, Forster CP, Krieglstein J (1979) Postgraduate Medical Journal 55 (suppl 1):7–10
4. Valenzuela JE, Defilippi C, Gutierrez F (1980) Digestive Disease and Science 25 (9): 716
5. Blackwell JN, Heading RC, Fettes HR (1981) Royal Society of Internal Medicine International Congress and Symposium Series 36:57