Não informado. Extension Folder. North Carolina State College of Agriculture and Engineering, Agricultural Extension Service.
Citação do estilo Chicago (17ª ed.)Não informado. Extension Folder. Raleigh, NC: North Carolina State College of Agriculture and Engineering, Agricultural Extension Service.
Citação MLA (8ª ed.)Não informado. Extension Folder. North Carolina State College of Agriculture and Engineering, Agricultural Extension Service.
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