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2. Bernstein, W. C.: Personal communication.
3. Committee on Pre and Postoperative Care (American College of Surgeons): Manual of Preoperative and Postoperative Care. Philadelphia, W. B. Saunders Company, 1967, p. 181.
4. Swinton, N. W.: Preoperative evaluation of the surgical patient (panel discussion). Dis. Colon Rectum.13: 175, 1970.