World Bank & ebrary, Inc. (2009). World Development Indicators. World Bank Publications.
Cita Chicago (17th ed.)World Bank i Inc ebrary. World Development Indicators. Washington: World Bank Publications, 2009.
Cita MLA (9th ed.)World Bank i Inc ebrary. World Development Indicators. World Bank Publications, 2009.
Atenció: Aquestes cites poden no estar 100% correctes.