Não informado. (1972). Education. National School Public Relations Association.
Chicago-Zitierstil (17. Ausg.)Não informado. Education. Washington: National School Public Relations Association, 1972.
MLA-Zitierstil (8. Ausg.)Não informado. Education. National School Public Relations Association, 1972.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.