ENGER ELDON D. (2013). ENVIRONMENTAL SCIENCE (13TH ED.). MC GRAW HILL.
Chicago Style aipamenaENGER ELDON D. ENVIRONMENTAL SCIENCE. 13TH ED. NEW YORK: MC GRAW HILL, 2013.
MLA aipamenaENGER ELDON D. ENVIRONMENTAL SCIENCE. 13TH ED. MC GRAW HILL, 2013.
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