Carey, R. G., & Posavac, E. J. (1989). Program evaluation: Methods and case studies (3.).
Chicago Style aipamenaCarey, Raymond G., and Emel J. Posavac. Program Evaluation: Methods and Case Studies. 3. New Jersey, Prentice Hall, 1989.
MLA aipamenaCarey, Raymond G., and Emel J. Posavac. Program Evaluation: Methods and Case Studies. 3. 1989.
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