APA (7th ed.) Citation

Ritter, F. E., Baxter, G. D., & Churchill, E. F. Foundations for desgning user-centered systems: What system designers need to know about people.

Chicago Style (17th ed.) Citation

Ritter, Frank E., Gordon D. Baxter, and Elizabeth F. Churchill. Foundations for Desgning User-centered Systems: What System Designers Need to Know About People.

MLA (8th ed.) Citation

Ritter, Frank E., et al. Foundations for Desgning User-centered Systems: What System Designers Need to Know About People.