APA (7th ed.) Zitazioa
O'Brien, D. (2004). Gk with derek the ultimate general knowledge and quiz com ndium: 2 business. PenguinBooks.
Chicago Style (17th ed.) Zitazioa
O'Brien, Derek. Gk with Derek the Ultimate General Knowledge and Quiz Com Ndium: 2 Business. New Delh: PenguinBooks, 2004.
MLA (9th ed.) Zitazioa
O'Brien, Derek. Gk with Derek the Ultimate General Knowledge and Quiz Com Ndium: 2 Business. PenguinBooks, 2004.
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