Buecher (III): "Hindenburg und Ludendorff als Feldherren" von Generalmajor a. D. Dr. h. c. v. Haeften Ludendorff, Box: 1, Folder: 29. German State Documents, RH MS 228. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/6555 Accessed March 23, 2025.