Levitt, S. D. (2005). Freakonomics: A rouge economist explores the hidden side of everything. Penguin Group.
Chicago-viite (17. p.)Levitt, Steven D. Freakonomics: A Rouge Economist Explores the Hidden Side of Everything. New York: Penguin Group, 2005.
MLA-viite (9. p.)Levitt, Steven D. Freakonomics: A Rouge Economist Explores the Hidden Side of Everything. Penguin Group, 2005.
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