APA (7th ed.) Citation

Sheckley, R., & Francis, D. (2009). Forever. Project Gutenberg.

Chicago Style (17th ed.) Citation

Sheckley, Robert, and Dick Francis. Forever. Project Gutenberg, 2009.

MLA (9th ed.) Citation

Sheckley, Robert, and Dick Francis. Forever. Project Gutenberg, 2009.

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