Frederick, R. W. (1959). The third curriculum: Student activities in American education. Appleton-Century-Crofts.
Chicago-Zitierstil (17. Ausg.)Frederick, Robert W. The Third Curriculum: Student Activities in American Education. New York: Appleton-Century-Crofts, 1959.
MLA-Zitierstil (9. Ausg.)Frederick, Robert W. The Third Curriculum: Student Activities in American Education. Appleton-Century-Crofts, 1959.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.