Creswell, J. W. (1994). Research design: Qualitative & quantitative approaches. Sage Publications.
Chicago Style aipamenaCreswell, John W. Research Design: Qualitative & Quantitative Approaches. Thousand Oaks, Calif.: Sage Publications, 1994.
MLA aipamenaCreswell, John W. Research Design: Qualitative & Quantitative Approaches. Sage Publications, 1994.
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