World Bank. 2011 World development indicators. The World Bank.
Chicagoスタイル(17版)引用形式World Bank. 2011 World Development Indicators. Washington, D.C.: The World Bank.
MLA(8版)引用形式World Bank. 2011 World Development Indicators. The World Bank.
警告: この引用は必ずしも正確ではありません.