Saunders, Mark
Research methods for business students
Prentice-Hall, 2003
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Saunders, Mark
Research methods for business students
Pearson Education, 2016
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Wiersma, William
Research methods in education: an introduction
Pearson/Allyn and Bacon, 2005
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Wiersma, William
Research methods in education: an introduction
Allyn and Bacon , 1991
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Wiersma, William
Research methods in education : an introduction
Pearson, 2009
 Buku Teks SO