APA (7th ed.) Citation

Wirt, M. A. (2012). The Missing Formula Madge Sterling Series, #1. Project Gutenberg.

Chicago Style (17th ed.) Citation

Wirt, Mildred A. The Missing Formula Madge Sterling Series, #1. Project Gutenberg, 2012.

MLA (9th ed.) Citation

Wirt, Mildred A. The Missing Formula Madge Sterling Series, #1. Project Gutenberg, 2012.

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