共 35 条
[2]
ALEXANDER FE, 1987, 11 SCI M INT EP ASS
[3]
THE CONCLUSION OF A 10-YEAR STUDY OF WATER FLUORIDATION
[J].
AMERICAN JOURNAL OF PUBLIC HEALTH AND THE NATIONS HEALTH,
1956, 46 (03)
:265-271
[4]
Black D., 1980, INEQUALITIES HLTH
[5]
BLAND JM, COMMUNICATION
[6]
THE DESIGN OF CONTROLLED EXPERIMENTS IN THE EVALUATION OF NON-THERAPEUTIC INTERVENTIONS
[J].
JOURNAL OF CHRONIC DISEASES,
1982, 35 (07)
:531-538
[7]
Cochran W.G., 2007, SAMPLING TECHNIQUES

