Não informado. (1926). Bulletin of the National Association of Secondary School Principals. National Association of Secondary School Principals.
Chicago-Zitierstil (17. Ausg.)Não informado. Bulletin of the National Association of Secondary School Principals. Washington: National Association of Secondary School Principals, 1926.
MLA-Zitierstil (8. Ausg.)Não informado. Bulletin of the National Association of Secondary School Principals. National Association of Secondary School Principals, 1926.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.