APA (7th ed.) Citation

Avila, D. L., Combs, A. W., & Purkey, W. W. (1972). The helping relationship sourcebook. Allyn and Bacon.

Chicago Style (17th ed.) Citation

Avila, Donald L., Arthur Wright Combs, and William Watson Purkey. The Helping Relationship Sourcebook. Boston: Allyn and Bacon, 1972.

MLA (9th ed.) Citation

Avila, Donald L., et al. The Helping Relationship Sourcebook. Allyn and Bacon, 1972.