APA-viite (7. p.)
Gardner, B. L. (2006). American agriculture in the twentieth century: How it flourished and what it cost. Harvard University Press.
Chicago-viite (17. p.)
Gardner, Bruce L. American Agriculture in the Twentieth Century: How It Flourished and What It Cost. Cambridge, MA: Harvard University Press, 2006.
MLA-viite (9. p.)
Gardner, Bruce L. American Agriculture in the Twentieth Century: How It Flourished and What It Cost. Harvard University Press, 2006.
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