1. Ectopic pregnancy — United States, 1987;Centers for Disease Control;MMWR,1990
2. Report on confidential enquiries into maternal deaths in the United Kingdom 1985–1987;Department of Health and Social Security,1991
3. History of Gynecology;Leonardo,1944
4. Ectopic pregnancy in Aberdeen 1950–1985;Flett;Br J Obstet Gynecol,1988
5. Risk factors for ectopic pregnancy;Marchbanks;JAMA,1988