Cooper, Donald R.
Business research methods
McGraw-Hill, 2001
 Buku Teks
Business research methods
by William G. Zikmund ... [and others]
South-Western Cengage Learning, 2013
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Cooper, Donald R.
Business research methods
McGraw-Hill, 2014
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Cooper, Donald R.
Business research methods
McGraw-Hil, 2003
 Multimedia
Cooper, Donald R.
Business research methods
Irwin, McGraw-Hill, 1998
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