1. Contractility of the human uterus recorded by new methods;Alvarez;Surg Gynecol Obstet,1950
2. The functional divisions of labor;Friedman;Am J Obstet Gynecol,1971
3. Dystocia due to abnormalities of the expulsive forces;Cunningham,1993
4. Conduct of normal labor and delivery;Cunningham,1993
5. Active management of labor;O'Driscoll,1993