World Bank. (2003). World development indicators. International Bank for Reconstruction and Development.
Cita Chicago (17th ed.)World Bank. World Development Indicators. Washington, D.C.: International Bank for Reconstruction and Development, 2003.
Cita MLA (9th ed.)World Bank. World Development Indicators. International Bank for Reconstruction and Development, 2003.
Atenció: Aquestes cites poden no estar 100% correctes.