APA (7e ed.) Bronvermelding
O'Brien Derek. (2004). Gk with Derek the ultimate general knowledge and quiz compendium: 1 history and geography. Penguin Books.
Chicago (17e ed.) Bronvermelding
O'Brien Derek. Gk with Derek the Ultimate General Knowledge and Quiz Compendium: 1 History and Geography. New Delhi: Penguin Books, 2004.
MLA (9e ed.) Bronvermelding
O'Brien Derek. Gk with Derek the Ultimate General Knowledge and Quiz Compendium: 1 History and Geography. Penguin Books, 2004.
Let op: Deze citaties zijn niet altijd 100% accuraat.