APA (7th ed.) Citation

Sierra, K. (2015). Badass: Making users awesome. O'Reilly Media.

Chicago Style (17th ed.) Citation

Sierra, Kathy. Badass: Making Users Awesome. Sebastopol, CA: O'Reilly Media, 2015.

MLA (9th ed.) Citation

Sierra, Kathy. Badass: Making Users Awesome. O'Reilly Media, 2015.

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