1. AfroBarometer Round 6 (2015). African Barometer:
http://afrobarometer.org/data
.
2. Arab Barometer Wave 3 (2017). Arab Barometer:
http://arabbarometer.org/instruments-and-data-files
.
3. Arab Transformations Survey 2014. (2017). University of Aberdeen:
http://www.arabtrans.eu
.
4. Corruption Perception Index. (2017). Transparency International:
http://www.transparency.org.uk/corruption/measuring-corruption/
.
5. Enterprise Surveys. (2017). World Bank:
http://www.enterprisesurveys.org
.