APA (7th ed.) Citation

Christie, A. (2007). The secret adversary. HarperCollins Publishers.

Chicago Style (17th ed.) Citation

Christie, Agatha. The Secret Adversary. London: HarperCollins Publishers, 2007.

MLA (9th ed.) Citation

Christie, Agatha. The Secret Adversary. HarperCollins Publishers, 2007.

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