Letter from [Count Karl Robert] Nesselrode, December 1, 1836 (St. Petersbourg [St. Petersburg]), Box: 22, Folder: 63. Letters, literary manuscripts, and personal papers of the Porter family, MS 28. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/467019 Accessed January 17, 2025.