APA (7th ed.) Citation

Wolf, M., & Emshwiller, E. (2010). The Very Secret Agent. Project Gutenberg.

Chicago Style (17th ed.) Citation

Wolf, Mari, and Ed Emshwiller. The Very Secret Agent. Project Gutenberg, 2010.

MLA (9th ed.) Citation

Wolf, Mari, and Ed Emshwiller. The Very Secret Agent. Project Gutenberg, 2010.

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