Gaya APA

Phillips, J, J., Phillips, P, P. (2012). Measuring ROI in learning & development : case studies from global organizations . USA: ASTD.

Gaya MLA

Phillips, Jack, J.., Phillips, Patricia, Pulliam. "Measuring ROI in learning & development : case studies from global organizations". USA: ASTD, 2012. Buku/Printed Material.