Não informado. (2016). Agronomic-Economic Research on Soils of the Tropics. North Carolina State University, Soil Science Department.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Agronomic-Economic Research on Soils of the Tropics. Raleigh, NC: North Carolina State University, Soil Science Department, 2016.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Agronomic-Economic Research on Soils of the Tropics. North Carolina State University, Soil Science Department, 2016.
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