APA (7th ed.) Zitazioa
O'Brien, D. (2004). Gk with Derek the ultimate general knowledge and quiz compendium: Sports and cinema. Penguin Books.
Chicago Style (17th ed.) Zitazioa
O'Brien, Derek. Gk with Derek the Ultimate General Knowledge and Quiz Compendium: Sports and Cinema. New Delhi: Penguin Books, 2004.
MLA (9th ed.) Zitazioa
O'Brien, Derek. Gk with Derek the Ultimate General Knowledge and Quiz Compendium: Sports and Cinema. Penguin Books, 2004.
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