APA (7th ed.) Citation

MacGill, P. (2006). The Red Horizon. Project Gutenberg.

Chicago Style (17th ed.) Citation

MacGill, Patrick. The Red Horizon. Project Gutenberg, 2006.

MLA (9th ed.) Citation

MacGill, Patrick. The Red Horizon. Project Gutenberg, 2006.

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