TWIST, C. Encyclopedia of science: The enviorement ecology, pollution, and agriculture. Volume VII. Macmillan Publishing Company.
Chicago-viite (17. p.)TWIST, Clint. Encyclopedia of Science: The Enviorement Ecology, Pollution, and Agriculture. Volume VII. Macmillan Publishing Company.
MLA-viite (8. p.)TWIST, Clint. Encyclopedia of Science: The Enviorement Ecology, Pollution, and Agriculture. Volume VII. Macmillan Publishing Company.
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