Gaya APA
Swanson, C, P., Martens, R. (NULL).
Social psychology & physical activity .
New:
New York: Harper & Row; 1975.
Gaya MLA
Swanson, Carl, P.., Martens, Rainer.
"Social psychology & physical activity".
New:
New York: Harper & Row; 1975,
NULL.
Text.