APA (7th ed.) Citation

Christie, A. (2010). The mysterious affair at styles. Project Gutenberg.

Chicago Style (17th ed.) Citation

Christie, Agatha. The Mysterious Affair at Styles. To be supplied: Project Gutenberg, 2010.

MLA (8th ed.) Citation

Christie, Agatha. The Mysterious Affair at Styles. Project Gutenberg, 2010.

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