Leedy, P. D. (1985). Practical research: Planning and design (3rd ed.). Macmillan.
Chicago Style aipamenaLeedy, Paul D. Practical Research: Planning and Design. 3rd ed. New York: Macmillan, 1985.
MLA aipamenaLeedy, Paul D. Practical Research: Planning and Design. 3rd ed. Macmillan, 1985.
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