Zichermann, G., & Cunningham, C. (2011). Gamification by design: Implementing game mechanics in web and mobile apps. Sebastopol, Calif.: O'Reilly Media.
Chicago Style CitationZichermann, Gabe, and Christopher Cunningham. Gamification By Design: Implementing Game Mechanics in Web and Mobile Apps. Sebastopol, Calif.: O'Reilly Media, 2011.
MLA CitationZichermann, Gabe, and Christopher Cunningham. Gamification By Design: Implementing Game Mechanics in Web and Mobile Apps. Sebastopol, Calif.: O'Reilly Media, 2011.
Warning: These citations may not always be 100% accurate.