APA (7th ed.) Citation

Smith, G. O., & Martinez. (2007). History Repeats. Project Gutenberg.

Chicago Style (17th ed.) Citation

Smith, George O., and Martinez. History Repeats. Project Gutenberg, 2007.

MLA (9th ed.) Citation

Smith, George O., and Martinez. History Repeats. Project Gutenberg, 2007.

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