APA (7th ed.) Citation

Christie, A. (1959). Poirot investigates ([5th printing].). Pan Books.

Chicago Style (17th ed.) Citation

Christie, Agatha. Poirot Investigates. [5th printing]. London: Pan Books, 1959.

MLA (9th ed.) Citation

Christie, Agatha. Poirot Investigates. [5th printing]. Pan Books, 1959.

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