Não informado. (1967). Phosphorus in agriculture. International Superphosphate and Compound Manufacturers Association.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Phosphorus in Agriculture. London: International Superphosphate and Compound Manufacturers Association, 1967.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Phosphorus in Agriculture. International Superphosphate and Compound Manufacturers Association, 1967.
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