Egan, G. (2010). The skilled helper: A problem-management and opportunity-development approach to helping (9th ed.). Brooks/Cole.
Chicago-viite (17. p.)Egan, Gerard. The Skilled Helper: A Problem-management and Opportunity-development Approach to Helping. 9th ed. Australia: Brooks/Cole, 2010.
MLA-viite (9. p.)Egan, Gerard. The Skilled Helper: A Problem-management and Opportunity-development Approach to Helping. 9th ed. Brooks/Cole, 2010.
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