1. The effect of a preventive programme on dental plaque, gingivitis and caries in schoolchildren. Results after one and two years
2. Caries experience as predictor for caries incidence
3. 3. J. V. Bradley: Distributionjree statistical tests . Prentice-Hall, London1968 , p.68 .
4. 4. G. W. Burnett, and H. W. Scherp: Oral microbiology and infectious disease . The Williams and Wilkins Company, Baltimore1968 , p.273 .
5. Longitudinal studies of the natural history of caries—II