Gaya APA
Cooper., D, R., Emory., C, W. (1995).
Business Research Methods (Fifth Edition.).
America:
Richrd . Irwin, INC.,.
Gaya MLA
Cooper., Donald, R.., Emory., C., William.
"Business Research Methods".
Fifth Edition.
America:
Richrd . Irwin, INC.,,
1995.
Text.