APA (7th ed.) Citation

Kobsa, A., & Wahlster, W. (1989). User Models in Dialog Systems. Springer Berlin Heidelberg.

Chicago Style (17th ed.) Citation

Kobsa, Alfred, and Wolfgang Wahlster. User Models in Dialog Systems. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989.

MLA (9th ed.) Citation

Kobsa, Alfred, and Wolfgang Wahlster. User Models in Dialog Systems. Springer Berlin Heidelberg, 1989.