Sackman, H. (1975). Delphi critique: Expert opinion, forecasting, and group process. Lexington Books.
Chicago-viite (17. p.)Sackman, Harold. Delphi Critique: Expert Opinion, Forecasting, and Group Process. Lexington, Mass: Lexington Books, 1975.
MLA-viite (9. p.)Sackman, Harold. Delphi Critique: Expert Opinion, Forecasting, and Group Process. Lexington Books, 1975.
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