APA (7th ed.) Citation

Kummer, F. A., & Grefé, W. (2012). The Blue Lights A Detective Story. Project Gutenberg.

Chicago Style (17th ed.) Citation

Kummer, Frederic Arnold, and Will Grefé. The Blue Lights A Detective Story. Project Gutenberg, 2012.

MLA (9th ed.) Citation

Kummer, Frederic Arnold, and Will Grefé. The Blue Lights A Detective Story. Project Gutenberg, 2012.

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