1. Operational definition of support;Anderson;JOGN Nursing,1976
2. Comprehensive maternity nursing: Perinatal and women's health;Auvenshine,1990
3. Mothers' perceptions of their labor;Butani;American Journal of Maternal Child Nursing,1980
4. Biofeedback relaxation training effects in childbirth;Gregg;Behavioral Engineering,1978
5. Psychological tensions in pregnancy;Grimm;Psychosomatic Medicine,1961