Não informado. (1950). Agricultural and horticultural Engineering abstracts. National Institute of Agricultural Engineering.
Chicago-referens (17:e uppl.)Não informado. Agricultural and Horticultural Engineering Abstracts. Silsoe, Inglaterra: National Institute of Agricultural Engineering, 1950.
MLA-referens (8:e uppl.)Não informado. Agricultural and Horticultural Engineering Abstracts. National Institute of Agricultural Engineering, 1950.
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