Não informado. West Virginia Agriculture and Forestry. University of West Virginia, College of Agriculture and Forestry.
Chicago-viite (17. p.)Não informado. West Virginia Agriculture and Forestry. Morgantown, Wa. Va: University of West Virginia, College of Agriculture and Forestry.
MLA-viite (8. p.)Não informado. West Virginia Agriculture and Forestry. University of West Virginia, College of Agriculture and Forestry.
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