APA (7th ed.) Citation

Pennell, J. (2012). Modern Illustration. Project Gutenberg.

Chicago Style (17th ed.) Citation

Pennell, Joseph. Modern Illustration. Project Gutenberg, 2012.

MLA (9th ed.) Citation

Pennell, Joseph. Modern Illustration. Project Gutenberg, 2012.

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