University of the Philippines (Los Banos). College of Agriculture & Department of Soils. A laboratory manual in soil science. s.n.
Chicago-viite (17. p.)University of the Philippines (Los Banos). College of Agriculture ja Department of Soils. A Laboratory Manual in Soil Science. [Los Banos, Laguna: s.n.
MLA-viite (9. p.)University of the Philippines (Los Banos). College of Agriculture ja Department of Soils. A Laboratory Manual in Soil Science. s.n.
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