Não informado. Spectator. National Association of Elementary School Principals.
Chicago-viite (17. p.)Não informado. Spectator. Arlington, Va: National Association of Elementary School Principals.
MLA-viite (8. p.)Não informado. Spectator. National Association of Elementary School Principals.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.