共 28 条
[2]
BERGMAN AB, 1972, PEDIATRICS, V49, P860
[3]
BERGMAN AB, 1970, 2ND P INT C CAUS SUD
[7]
FLEISS JL, 1981, STATISTICAL METHODS, P244
[8]
FROGGATT P, 1971, BRIT J PREV SOC MED, V25, P119
[10]
HUNT CE, 1983, J PEDIATR, V103, P967