Não informado. (2007). Annual report of the Director to the Board of Trustees. Chicago Natural History Museum.
Chicago-viite (17. p.)Não informado. Annual Report of the Director to the Board of Trustees. Chicago, Ill: Chicago Natural History Museum, 2007.
MLA-viite (8. p.)Não informado. Annual Report of the Director to the Board of Trustees. Chicago Natural History Museum, 2007.
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