APA (7th ed.) Zitazioa
Geer, J. G. (2006). In defense of negativity: Attack ads in presidential campaigns. University of Chicago Press.
Chicago Style (17th ed.) Zitazioa
Geer, John Gray. In Defense of Negativity: Attack Ads in Presidential Campaigns. Chicago: University of Chicago Press, 2006.
MLA (9th ed.) Zitazioa
Geer, John Gray. In Defense of Negativity: Attack Ads in Presidential Campaigns. University of Chicago Press, 2006.
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