Gaya APA
Creswell, J, W. (2012).
Educational Research; Palning, conduting and evaluating quantitative and qualitative research (edisi 4).
University of braska- lincoln:
Pearson.
Gaya MLA
Creswell, Jhon, W..
"Educational Research; Palning, conduting and evaluating quantitative and qualitative research".
edisi 4
University of braska- lincoln:
Pearson,
2012.
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