World Bank & ebrary, Inc. (2009). World Development Indicators. World Bank Publications.
Chicago Style (17th ed.) ZitazioaWorld Bank eta Inc ebrary. World Development Indicators. Washington: World Bank Publications, 2009.
MLA (9th ed.) ZitazioaWorld Bank eta Inc ebrary. World Development Indicators. World Bank Publications, 2009.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.