Letter from Sturm, Francis and John Sturm to John Gould Monograph of the Ramphastidae Prospectus in German, November 12, 1842, Box: 3, Folder: 2. Letters of John Gould, MS 313. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/186754 Accessed May 25, 2024.