APA (7th ed.) Citation

Winterbotham, R. R. (2007). The Whispering Spheres. Project Gutenberg.

Chicago Style (17th ed.) Citation

Winterbotham, R. R. The Whispering Spheres. Project Gutenberg, 2007.

MLA (9th ed.) Citation

Winterbotham, R. R. The Whispering Spheres. Project Gutenberg, 2007.

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