APA (7th ed.) Citation

Walker, R. (2013). The Phantom Airman. Project Gutenberg.

Chicago Style (17th ed.) Citation

Walker, Rowland. The Phantom Airman. Project Gutenberg, 2013.

MLA (9th ed.) Citation

Walker, Rowland. The Phantom Airman. Project Gutenberg, 2013.

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