共 26 条
[1]
ANDERSEN BL, 1983, OBSTET GYNECOL, V62, P457
[4]
ANDREASSON B, ACTA OBSTET GYNECOL
[5]
ARMITAGE P, 1977, STATISTICAL METHODS, P380
[6]
BARNES AE, 1980, OBSTET GYNECOL, V56, P234
[8]
CHU J, 1982, OBSTET GYNECOL, V59, P716