- UNESCO, UIS Statistics
- Barro and Lee (2013) educational attainment data
- Cohen and Soto (2007) educational attainment data
- Wail, B., S. Hanchane, and A. Kamal (2012) education inequality data
- World Bank, World Development Indicators
- Research Institute for History and Culture of Utrecht University, Human Capital Hub data
- UNU-WIDER, World Income Inequality Database
