World Bank. (2009). Global economic prospects: Commodities at the crossroads. World Bank.
Chicago Style aipamenaWorld Bank. Global Economic Prospects: Commodities at the Crossroads. Washington, DC: World Bank, 2009.
MLA aipamenaWorld Bank. Global Economic Prospects: Commodities at the Crossroads. World Bank, 2009.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.