1. Intrapartum fetal monitoring–a disappointing story;Freeman;N Engl J Med,1990
2. Randomized controlled trial of cardiotocography versus Doppler auscultation of fetal heart at admission in labour in low risk obstetric population;Mires;BMJ,2001
3. Fetal heart rate patterns: monitoring, interpretation, and management. Number 207–July 1995 (replaces No. 132, September 1989);ACOG technical bulletin;Int J Gyneacol Obstet,1995
4. SOGC clinical practice guideline: Fetal health surveillance in labor. No. 112, March 2002, Society of Obstetricians and Gynaecologists of Canada, Vancouver, BC.
5. Electronic fetal heart rate monitoring: research guidelines for interpretation;National institute of Child Health and Human Development Research Planning Workshop;Am J Obstet Gynecol,1997