Egan, G. (1990). The skilled helper: A systematic approach to effective helping (4th ed.). Brooks / Cole.
Lua i Stíl Chicago (17ú heag.)Egan, Gerard. The Skilled Helper: A Systematic Approach to Effective Helping. 4th ed. California: Brooks / Cole, 1990.
Lua MLA (9ú heag.)Egan, Gerard. The Skilled Helper: A Systematic Approach to Effective Helping. 4th ed. Brooks / Cole, 1990.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.