Gaya APA

COOPER, D, R., Schindler, P, S. (2006). BUSINESS RESEARCH METHODS NINTH EDITION . BOSTON: Mc Graw Hill.

Gaya MLA

COOPER, DONALD, R.., Schindler, Pamela, S.. "BUSINESS RESEARCH METHODS NINTH EDITION". BOSTON: Mc Graw Hill, 2006. Text.