1. Gallstone prevalence and cholecystectomy rates are independently variable;Bateson;Lancet,1984
2. The natural history of gallstones: the innocent gallstone is not a myth;Gracie;N Engl J Med,1982
3. Changes in gallstone morbidity in a community with a decreasing frequency of cholecystectomy;Ahlberg;Acta Chir Scand,1984
4. Oral Contraceptive Study Oral contraceptives and gallbladder disease;Royal College of General Practitioners;Lancet,1982