Cita APA (7th ed.)
Gardner, B. L. (2006). American agriculture in the twentieth century: How it flourished and what it cost. Harvard University Press.
Cita Chicago (17th ed.)
Gardner, Bruce L. American Agriculture in the Twentieth Century: How It Flourished and What It Cost. Cambridge, MA: Harvard University Press, 2006.
Cita MLA (9th ed.)
Gardner, Bruce L. American Agriculture in the Twentieth Century: How It Flourished and What It Cost. Harvard University Press, 2006.
Atenció: Aquestes cites poden no estar 100% correctes.