Dyfyniad APA
World Bank & ebrary, Inc. (2011). World development indicators 2011. World Bank.
Dyfyniad Arddull Chicago
World Bank and Inc ebrary. World Development Indicators 2011. Washington, D.C.: World Bank, 2011.
Dyfyniad MLA
World Bank and Inc ebrary. World Development Indicators 2011. World Bank, 2011.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.