APA (7th ed.) Citation

Freeman, E., Bates, B., Freeman, E., & Sierra, K. (2004). Head First Design Patterns. O ' Reilly.

Chicago Style (17th ed.) Citation

Freeman, Eric, Bert Bates, Elisabeth Freeman, and Kathy Sierra. Head First Design Patterns. Beijing: O ' Reilly, 2004.

MLA (8th ed.) Citation

Freeman, Eric, et al. Head First Design Patterns. O ' Reilly, 2004.