Kupchella, C. I., & Kupchella, C. I. (1986). Environmental Science: Living Within System Of Nature / Charles E. Kupchella. Allyn and Bacon.
Chicago-viite (17. p.)Kupchella, Charles I., ja Charles I. Kupchella. Environmental Science: Living Within System Of Nature / Charles E. Kupchella. Allyn and Bacon, 1986.
MLA-viite (8. p.)Kupchella, Charles I., ja Charles I. Kupchella. Environmental Science: Living Within System Of Nature / Charles E. Kupchella. Allyn and Bacon, 1986.
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