Letter from Sturm, Francis and John Sturm to John Gould regarding the Monograph of the Ramphastidae Prospectus in German, July 31, 1841, Box: 3, Folder: 1. Letters of John Gould, MS 313. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/186753 Accessed May 18, 2024.