1. Barnett, W. S. (2002). Early childhood education. In A. Molnar (Ed.), School reform proposals: The research evidence (2nd ed.). Greenwich, CT: Information Age Publishing.
2. Britto, P. R. (2017). Early moments matter for every child. New York, NY: UNICEF: Retrieved https://www.unicef.org/media/files/UNICEF_Early_Moments_Matter_for_Every_Child_report.pdf.
3. Buchmann, C. (2000). Family structure, parental perceptions, and child labor in Kenya: What factors determine who is enrolled in school? Social Forces,78(4), 1349–1378. https://doi.org/10.1093/sf/78.4.1349.
4. Central Statistical Agency. (2012). 2007 Population and housing census of Ethiopia. Addis Ababa: Ethiopia. Retrieved from http://www.csa.gov.et/census-report/complete-report/census-2007.
5. Central Statistical Agency. (2013). Population projections for Ethiopia 2007–2037. Addis Ababa: Ethiopia. Retrieved from http://www.csa.gov.et/census-report/population-projections/category/368-population-projection-2007-2037.