Diedrich, R. C. (1972). Group procedures: purposes, processes, and outcomes: Selected readings for the counselor. Houghton Mifflin Company.
Chicago-viite (17. p.)Diedrich, Richard C. Group Procedures: Purposes, Processes, and Outcomes: Selected Readings for the Counselor. Boston: Houghton Mifflin Company, 1972.
MLA-viite (9. p.)Diedrich, Richard C. Group Procedures: Purposes, Processes, and Outcomes: Selected Readings for the Counselor. Houghton Mifflin Company, 1972.
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