Cita APA (7a ed.)
O'Brien Derek. (2004). Gk with Derek the ultimate general knowledge and quiz compendium: 1 history and geography. Penguin Books.
Cita Chicago Style (17a ed.)
O'Brien Derek. Gk with Derek the Ultimate General Knowledge and Quiz Compendium: 1 History and Geography. New Delhi: Penguin Books, 2004.
Cita MLA (9a ed.)
O'Brien Derek. Gk with Derek the Ultimate General Knowledge and Quiz Compendium: 1 History and Geography. Penguin Books, 2004.
Precaución: Estas citas no son 100% exactas.