1. Kostlan J Oral health services in Europe. Copenhagen: WHO Regional publications, European Series. No 50 1979.
2. Petersen PE Oral health behaviour of 6-year-old Danish children. Acta Odont Scand 1992; 50: 57–64.
3. Hescot P, Roland E Dental health in France 1993. DMF score for 6-9 and 12-year-olds. Paris: French Union for Oral Health 1993.
4. O'Brien M Childrens Dental Health in the United Kingdom 1993. London: Office of Population Censuses and Surveys, HMSO 1994.
5. Aleksejuniene J Dental caries and caries determinants in 7-12 and 15-year-old Lithuanians (thesis). OSLO, Norway: University of OSLO 1995.