Gaya APA

Gravetter, F, J., Forzano, L, B. (2009). Research Methods for the Behavioral Sciences 3'rd Ed. (3). USA: Wadsworth Cengage Learning.

Gaya MLA

Gravetter, Frederick, J.., Forzano, Lori-Ann, B.. "Research Methods for the Behavioral Sciences 3'rd Ed.". 3 USA: Wadsworth Cengage Learning, 2009. Text.