AEC/LGO Study of Natural Radioactivity in the Waters of the AmazonUnited States. National Archives and Records AdministrationSCI_Box3099SCI_28_Hydrology_1-1-64_BRAZ1965-01-18airgramsRadioactivityAmazon BasinUnited States. Department of StateAmembassy Rio de JaneiroDeptel 898 of 1/6/65; Embtel 1415 of 1/8/65; Deptel 915 of 1/11/65Simonpietri, Andre C.Author