Não informado. (1951). Fertilizers. Food and Agriculture Organization of the United Nations.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Fertilizers. Rome: Food and Agriculture Organization of the United Nations, 1951.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Fertilizers. Food and Agriculture Organization of the United Nations, 1951.
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