[6]
Nonpharmacologic relief of pain during labor: Systematic reviews of five methods[J] . Penny P. Simkin,MaryAnn O’Hara.American Journal of Obstetrics and Gynecology . 2002 (5)
[6]
Nonpharmacologic relief of pain during labor: Systematic reviews of five methods[J] . Penny P. Simkin,MaryAnn O’Hara.American Journal of Obstetrics and Gynecology . 2002 (5)