Barrezueta-Unda, S. (2019). Properties of several soils cultivated with cocoa in the province of El Oro, Ecuador. Universidad Autónoma de Tamaulipas.
Chicago-viite (17. p.)Barrezueta-Unda, Salomón. Properties of Several Soils Cultivated with Cocoa in the Province of El Oro, Ecuador. Universidad Autónoma de Tamaulipas, 2019.
MLA-viite (8. p.)Barrezueta-Unda, Salomón. Properties of Several Soils Cultivated with Cocoa in the Province of El Oro, Ecuador. Universidad Autónoma de Tamaulipas, 2019.
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