Barker, D. J. (1991). An economic analysis of farming coffee and trees at Turrialba, Costa Rica: Comparing small farms with poro (Erythrina poeppigiana) only to those with both laurel (Cordia alliodora) and poro.
Chicago-tyylinen lähdeviittausBarker, David J. An Economic Analysis of Farming Coffee and Trees At Turrialba, Costa Rica: Comparing Small Farms With Poro (Erythrina Poeppigiana) Only to Those With Both Laurel (Cordia Alliodora) and Poro. 1991.
MLA-viiteBarker, David J. An Economic Analysis of Farming Coffee and Trees At Turrialba, Costa Rica: Comparing Small Farms With Poro (Erythrina Poeppigiana) Only to Those With Both Laurel (Cordia Alliodora) and Poro. 1991.
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