共 4 条
[1]
DANZER H, 1980, FERTIL STERIL, V34, P336
[3]
KALLEN B, 1987, EUR J OBSTET GYN R B, V26, P291
[4]
KAUPPILA A, 1979, BMJ-BRIT MED J, V1, P1670, DOI 10.1136/bmj.1.6179.1670