Letters sent to Martha "Mattie" Baird Nicholson (Kate's mother, Blackmar's Mother-in-Law), 1863-1866; 1891, Box: 1, Folder: 8. Personal Papers of Frank Blackmar, PP 53. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/252817 Accessed May 24, 2024.