APA (7th ed.) Citation

Christie, A. (1999). The unexpected guest. HarperCollins Publishers.

Chicago Style (17th ed.) Citation

Christie, Agatha. The Unexpected Guest. New York: HarperCollins Publishers, 1999.

MLA (9th ed.) Citation

Christie, Agatha. The Unexpected Guest. HarperCollins Publishers, 1999.

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