共 21 条
[7]
Forrest J D, 1996, Obstet Gynecol Surv, V51, pS30, DOI 10.1097/00006254-199612000-00012
[9]
GRIMES DA, 2007, COCHRANE DB SYST REV
[10]
Unintended pregnancy in the United States
[J].
FAMILY PLANNING PERSPECTIVES,
1998, 30 (01)
:24-+