APA (7th ed.) Citation

Lewis, J. (2010). An Atheist Manifesto. Project Gutenberg.

Chicago Style (17th ed.) Citation

Lewis, Joseph. An Atheist Manifesto. Project Gutenberg, 2010.

MLA (9th ed.) Citation

Lewis, Joseph. An Atheist Manifesto. Project Gutenberg, 2010.

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