National Association of Elementary School Principals (U.S.). (1980). Principal. National Association of Elementary School Principals.
Chicago-referens (17:e uppl.)National Association of Elementary School Principals (U.S.). Principal. Arlington, Va.: National Association of Elementary School Principals, 1980.
MLA-referens (9:e uppl.)National Association of Elementary School Principals (U.S.). Principal. National Association of Elementary School Principals, 1980.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.