1. Perforated peptic ulcer, gastric and duodenal;Bierring;Acta chir. scandinav.,1955
2. Progress after perforated peptic ulcer;Illingworth;Brit. M. J.,1946
3. Perforated peptic ulcer: the results of treatment in the Netherlands (1934–1950): An analysis of 25,551 cases;Noordijk;Arch. chir. neerl.,1953
4. Follow-up study of 500 patients with chronic duodenal ulcer admitted to a veterans hospital;Thomson;Surg. Gynec. & Obst.,1960
5. To what extent should gastric resection be resorted to in perforating ulcer?;Troell;Acta chir. scandinav.,1954