APA (7th ed.) Citation

Riis, J. A. (2010). Is There a Santa Claus? Project Gutenberg.

Chicago Style (17th ed.) Citation

Riis, Jacob A. Is There a Santa Claus? Project Gutenberg, 2010.

MLA (9th ed.) Citation

Riis, Jacob A. Is There a Santa Claus? Project Gutenberg, 2010.

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