共 57 条
[2]
[Anonymous], 1972, Lancet, V2, P441
[3]
BALLARD RM, 1973, J OBSTET GYN BR COMM, V80, P469
[5]
BONNAR J, 1972, LANCET, V1, P614
[6]
BROWSE NL, 1969, LANCET, V2, P718
[9]
CHARNLEY J, 1972, LANCET, V2, P134