O. Fräki

Cumulative 10-year risk of symptomatic duodenal and gastric ulcer in patients with or without chronic gastritis. A clinical follow-up study of 454 outpatients.

P. Sipponen, U. M. Korri, M. Siurala, 1990, Scandinavian journal of gastroenterology.

Resection of the pancreas for acute fulminant pancreatitis.

E. Kivilaakso, P. Nikki, M. Lempinen, 1981, Surgery, gynecology & obstetrics.