Harlow, W. M. (1957). Trees of the eastern and central United States and Canada. Dover.
Chicago-viite (17. p.)Harlow, William M. Trees of the Eastern and Central United States and Canada. Nueva York: Dover, 1957.
MLA-viite (9. p.)Harlow, William M. Trees of the Eastern and Central United States and Canada. Dover, 1957.
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