Gaya APA
Gravetter, F., Forzano, L, B. (2018).
Research Methods for the Behavioral Sciens (Edition 6).
Mexico:
Salemba Humanika.
Gaya MLA
Gravetter, Frederick., Forzano, Lorri-Ann, B..
"Research Methods for the Behavioral Sciens".
Edition 6
Mexico:
Salemba Humanika,
2018.
Text.