Não informado. (2020). Reports of the Secretary and Treasurer. John Simon Guggenheim Memorial Foundation.
Chicago-referens (17:e uppl.)Não informado. Reports of the Secretary and Treasurer. New York: John Simon Guggenheim Memorial Foundation, 2020.
MLA-referens (8:e uppl.)Não informado. Reports of the Secretary and Treasurer. John Simon Guggenheim Memorial Foundation, 2020.
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