APA (7th ed.) Citation

Cox, I. E., & Dongen, H. R. v. (2008). The Guardians. Project Gutenberg.

Chicago Style (17th ed.) Citation

Cox, Irving E., and H. R. van Dongen. The Guardians. Project Gutenberg, 2008.

MLA (9th ed.) Citation

Cox, Irving E., and H. R. van Dongen. The Guardians. Project Gutenberg, 2008.

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