共 13 条
[2]
BELL ET, 1965, LANCET, V1, P1029
[3]
CAMPBELL S, 1971, J OBSTET GYN BR COMM, V78, P513
[4]
CAMPBELL S, 1969, Journal of Obstetrics and Gynaecology of the British Commonwealth, V76, P603
[5]
DONALD I, 1969, J PEDIATR-US, V75, P326
[9]
JOUPPILA P, 1971, ACTA OBSTETRICIA S15, V50
[10]
DETECTION OF FETAL HEART MOVEMENT IN FIRST TRIMESTER OF PREGNANCY USING PULSED ULTRASOUND
[J].
BMJ-BRITISH MEDICAL JOURNAL,
1972, 4 (5838)
:466-+