共 48 条
[1]
*AM COLL OBST GYN, 1991, STAND OBST GYN SERV
[3]
BERKI SE, 1987, PEDIATRICS, V79, P874
[5]
CAREY TS, 1991, HEALTH SERV RES, V26, P165
[7]
Clarke LL, 1999, HEALTH SERV RES, V34, P145
[9]
*DEP HLTH ENV CONT, 1995, VIT MORB STAT 1995
[10]
*DEP HLTH ENV CONT, 1994, VIT MORB STAT 1994