Hickling, Grace. Northumbria Nat.Hist.Soc. [The Natural History Society of Northumbria], Box: 4, Folder: 9. Sauer's Gouldiana Research about John Gould and other papers, MS 304. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/204425 Accessed November 24, 2024.