Não informado. Tropical Soils Research Program, Annual Report. North Carolina State University, Soil Science Department.
Chicago-viite (17. p.)Não informado. Tropical Soils Research Program, Annual Report. Raleigh, NC: North Carolina State University, Soil Science Department.
MLA-viite (8. p.)Não informado. Tropical Soils Research Program, Annual Report. North Carolina State University, Soil Science Department.
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