Não informado. (2020). Reports of the Secretary and Treasurer. John Simon Guggenheim Memorial Foundation.
Chicago-viite (17. p.)Não informado. Reports of the Secretary and Treasurer. New York: John Simon Guggenheim Memorial Foundation, 2020.
MLA-viite (8. p.)Não informado. Reports of the Secretary and Treasurer. John Simon Guggenheim Memorial Foundation, 2020.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.