1) Ohshima A, et al: Evaluation of a mass screening program for stomach cancer with a case-control study design, Int J Cancer: 38, 829-833, 1986.
2) Samloff IM, et al: Relationships among serum pepsinogen I, serum pepsinogen II, and gastric mucosal histology-a study in relatives of patients with pernicious anemia, Gastroenterology: 83, 204-209, 1982.