1. Prevalence of sleep/wake disturbances in Sydney adolescents;Bearpark;Sleep Res.,1987
2. Diagnostic Interview Schedule for Children (DISC);Costello,1982
3. A socio-economic index for New Zealand based on levels of education and income from the 1966 census;Elley;N.Z. J. Educ. Stud.,1972
4. The Analysis of Contingency Tables;Everitt,1977
5. Epidemiological study of sleep disturbances and psychiatric disorders: an opportunity for prevention?;Ford;JAMA,1989