National Association of Elementary School Principals (U.S.). (1980). Principal. National Association of Elementary School Principals.
Chicago-viite (17. p.)National Association of Elementary School Principals (U.S.). Principal. Arlington, Va.: National Association of Elementary School Principals, 1980.
MLA-viite (9. p.)National Association of Elementary School Principals (U.S.). Principal. National Association of Elementary School Principals, 1980.
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