APA (7th ed.) Zitazioa
O'Brien, D. (2004). Gk with derek the ultimate general knowledge and quiz compendium: 4 india. Penguin Books.
Chicago Style (17th ed.) Zitazioa
O'Brien, Derek. Gk with Derek the Ultimate General Knowledge and Quiz Compendium: 4 India. New Delhi: Penguin Books, 2004.
MLA (9th ed.) Zitazioa
O'Brien, Derek. Gk with Derek the Ultimate General Knowledge and Quiz Compendium: 4 India. Penguin Books, 2004.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.