APA (7th ed.) Citation

Younger, C. (2008). The Story of Cole Younger, by Himself. Project Gutenberg.

Chicago Style (17th ed.) Citation

Younger, Cole. The Story of Cole Younger, by Himself. Project Gutenberg, 2008.

MLA (9th ed.) Citation

Younger, Cole. The Story of Cole Younger, by Himself. Project Gutenberg, 2008.

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