Friedman, T. L. (2009). Hot, flat, and crowded: Why we need a green revolution, and how it can renew America. Penguin.
Chicago-viite (17. p.)Friedman, Thomas L. Hot, Flat, and Crowded: Why We Need a Green Revolution, and How It Can Renew America. New York: Penguin, 2009.
MLA-viite (9. p.)Friedman, Thomas L. Hot, Flat, and Crowded: Why We Need a Green Revolution, and How It Can Renew America. Penguin, 2009.
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