Combs, A. W., Purkey, W. W., & Avila, D. L. (1978). Helping relationships: Basic concepts for the helping professions (2nd ed.). Allyn and Bacon.
Citazione stile Chigago Style (17a edizione)Combs, Arthur W., William W. Purkey, e Donald L. Avila. Helping Relationships: Basic Concepts for the Helping Professions. 2nd ed. Boston: Allyn and Bacon, 1978.
Citatione MLA (9a ed.)Combs, Arthur W., et al. Helping Relationships: Basic Concepts for the Helping Professions. 2nd ed. Allyn and Bacon, 1978.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.