Não informado. (1920). Milk Industry. National Dairymen's Association.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Milk Industry. London: National Dairymen's Association, 1920.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Milk Industry. National Dairymen's Association, 1920.
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