APA (7th ed.) Citation

Sheldon, W. J. (2009). Houlihan's Equation. Project Gutenberg.

Chicago Style (17th ed.) Citation

Sheldon, Walter J. Houlihan's Equation. Project Gutenberg, 2009.

MLA (9th ed.) Citation

Sheldon, Walter J. Houlihan's Equation. Project Gutenberg, 2009.

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