APA (7th ed.) Citation

Robert Allen, E. (2010). The New Penguin English dictionary. Penguin.

Chicago Style (17th ed.) Citation

Robert Allen, Edit. The New Penguin English Dictionary. Penguin, 2010.

MLA (8th ed.) Citation

Robert Allen, Edit. The New Penguin English Dictionary. Penguin, 2010.

Warning: These citations may not always be 100% accurate.