Putt, A. D. (1989). Policy research: Concepts, methods, and applications. Prentice Hall.
Chicago Style aipamenaPutt, Allen D. Policy Research: Concepts, Methods, and Applications. Englewood Cliffs, N.J: Prentice Hall, 1989.
MLA aipamenaPutt, Allen D. Policy Research: Concepts, Methods, and Applications. Prentice Hall, 1989.
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