Skudutyte-Rysstad, R., H. M. Eriksen, and E. Bjertness. “Oral Health Among 35-Year-Olds in Oslo, Norway. A Summary of Time Trends 1973-2003”. Norsk Epidemiologi, vol. 22, no. 1, May 2012, doi:10.5324/nje.v22i1.1518.