共 8 条
[3]
LETT WJ, 1977, J REPROD MED, V19, P51
[4]
MENDELSON J, 1979, OBSTET GYNECOL, V53, P31
[5]
POLK BF, 1980, LANCET, V1, P437
[8]
SWARTZ WH, 1979, OBSTET GYNECOL, V54, P284