APA (7th ed.) Citation

Burroughs, E. R. (2010). A princess of mars. Project Gutenberg.

Chicago Style (17th ed.) Citation

Burroughs, Edgar Rice. A Princess of Mars. To be supplied: Project Gutenberg, 2010.

MLA (8th ed.) Citation

Burroughs, Edgar Rice. A Princess of Mars. Project Gutenberg, 2010.

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