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2. Nutrient requirements of small ruminants; sheep, goats, cervids and New World camelids,2007
3. Water requirements for livestock;Alberta Agriculture Food and Rural Development Extension Bulletin,2000
4. When is water good enough for livestock;Bauder;Montana State Extension Bulletin,2000
5. Guyer PQ: Livestock water quality, University of Nebraska Extension Service Bulletin G79-46A.