National Association of Elementary School Principals (U.S.). (1980). Principal. National Association of Elementary School Principals.
Lua i Stíl Chicago (17ú heag.)National Association of Elementary School Principals (U.S.). Principal. Arlington, Va.: National Association of Elementary School Principals, 1980.
Lua MLA (9ú heag.)National Association of Elementary School Principals (U.S.). Principal. National Association of Elementary School Principals, 1980.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.