1. Essential obstetric practice;Amiel,1981
2. Parturitional posture and related birth behavior;Atwood;Acta Obstetrica et Gynecologica Scandinavica,1976
3. Mayes' Midwifery—A textbook for midwives;Bailey,1976
4. Obstetrics and the newborn;Beischer,1986
5. Obstetrics for pupil midwives;Bender,1972