Creswell, J. W. (2009). Research design: Qualitative, quantitative, and mixed methods approaches (3rd ed.). Sage Publications.
Chicago-viite (17. p.)Creswell, John W. Research Design: Qualitative, Quantitative, and Mixed Methods Approaches. 3rd ed. Thousand Oaks, Calif.: Sage Publications, 2009.
MLA-viite (8. p.)Creswell, John W. Research Design: Qualitative, Quantitative, and Mixed Methods Approaches. 3rd ed. Sage Publications, 2009.
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