1. Jensen, H.-E., Amdrup, E.: Follow-up of 100 patients five to eight years after parietal cell vagotomy. World J. Surg.2:525, 1978
2. Græm, N., Fischer, A.B., Hastrup, N., Povlsen, C.O.: Mucosal changes of the Billroth II resected stomach. Acta Pathol. Microbiol. Scand. [Sect. A]89:227, 1981
3. Fischer, A.B., Græm, N., Jensen, O.M.: Risk of gastric cancer after Billroth II resection for duodenal ulcer. Br. J. Surg.70:552, 1983
4. Fischer, A.B., Knop, J., Græm, N.: Late mortality following Billroth II resection for duodenal ulcer. (in press)
5. Siegel, S.: Non-parameter Statistics for Behavioral Sciences. New York, McGraw-Hill, 1956