共 5 条
[1]
BYGDEMAN M, 1989, ACTA OBSTET GYN SCAN, P13
[2]
FRIEDMAN T, 1989, J ROY COLL GEN PRACT, V39, P456
[3]
Hertig AT, 1944, NEW ENGL J MED, V230, P797
[5]
1990, LANCET, V336, P1480