1. Abortion surveillance—United States, 2003;Strauss;Morb Mortal Wkly Rep Surveill Summ,2006
2. Second-trimester abortion by dilatation and evacuation: an analysis of 11,747 cases;Peterson;Obstet Gynecol,1983
3. A Clinician's Guide to Medical and Surgical Abortion;Haskell,1999
4. Mechanical methods of cervical ripening;Krammer;Clin Obstet Gynecol,1995
5. Preparation of the cervix: hydrophilic and prostaglandin dilators;Darney;Clin Obstet Gynecol,1986