共 18 条
[12]
SCHOLL TO, 1990, OBSTET GYNECOL, V75, P948
[13]
SIBAI BM, 1984, OBSTET GYNECOL, V64, P319
[14]
SIBAI BM, 1991, AM J OBSTET GYNECOL, V165, P1408
[15]
Sokal R. R., 1987, INTRO BIOSTATISTICS
[16]
STONE JL, 1994, OBSTET GYNECOL, V83, P357
[17]
*WHO, 1987, WHO TECHN REP SER, V758