COOPER D R. (2001). BUSINESS RESEARCH METHODS (6TH.). TATA MCGRAW-HILL PUBLISHING COMPANY.
Cita Chicago (17th ed.)COOPER D R. BUSINESS RESEARCH METHODS. 6TH. NEW DELHI: TATA MCGRAW-HILL PUBLISHING COMPANY, 2001.
Cita MLA (9th ed.)COOPER D R. BUSINESS RESEARCH METHODS. 6TH. TATA MCGRAW-HILL PUBLISHING COMPANY, 2001.
Atenció: Aquestes cites poden no estar 100% correctes.