1. Hermanek P, Sobin LH, eds. UICC TNMClassification of Malignant Tumours, 4th ed., Springer-Verlag, Berlin, 1987.
2. Zerbi A, Balzano G, Bottura R, Di Carlo, V. Reliability of pancreatic cancer staging classifications.Int J Pancreatol 1994; 15: 13–18.
3. Tsunoda T, Ura K, Eto T, Matsumoto T, Tsuchiya R. UICC and Japanese stage classification for carcinoma of the pancreas.Int J Pancreatol 1991; 8: 205–214.
4. Bassi C, Butturini G, Falconi M, Iacono C, Serio G, Pederzoli P. Staging of pancreatic cancer: suggestions for a simplified, reliable modification of the TNM classification system.Int J Pancreatol 1995; 17: 213,214.
5. Klöppel G, Lingenthal G, von Bülow M, Kern HF. Histological and fine structural features of pancreatic ductal adenocarcinomas in relation to growth and prognosis: studies in xenografted tumours and clinicopathological correlation in a series of 75 casesHistopathology 1985; 9: 841–856.