Palys, T.S. (Theodore Stephen)
Research decisions : quantitative, qualitative, and mixed method approaches
Nelson Education, 2014
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Creswell, John W.
Research design : qualitative, quantitative, and mixed methods approaches
Sage Publication, Inc, 2003
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Creswell, John W.
Research design : qualitative, quantitative, and mixed methods approaches
Sage, 1994
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Creswell, John W.
Research design : qualitative, quantitative, and mixed methods approaches
Sage, 2018
 Buku Teks
Creswell, John W.
Research design : qualitative, quantitative, and mixed methods approaches
Sage, 2014
 Buku Teks