From February 25, color notes beginning "blue-cobalt", sketches, Folder: 11, item: 2. Papers of Lady Pauline Trevelyan, 1827-1866, and other family members, 1809-1879, Great Britain and Europe, MS C133. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/215625 Accessed May 17, 2024.