Valdes, A., Ramos, H., & Schaeffer, B. (1996). Surveillance of agricultural price and trade policies: A handbook for Ecuador. World Bank.
Chicago-viite (17. p.)Valdes, Alberto, Hugo Ramos, ja Barry Schaeffer. Surveillance of Agricultural Price and Trade Policies: A Handbook for Ecuador. Washington, D.C: World Bank, 1996.
MLA-viite (9. p.)Valdes, Alberto, et al. Surveillance of Agricultural Price and Trade Policies: A Handbook for Ecuador. World Bank, 1996.
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