1855-1856 Box 14, Folder 4 Series I: Personal, 1847-1925Subseries I.2: Biographical Materials, 1847-1925Course WorkUniversity of Göttingen
1860-1925 Box 1, Folder 24 to 27 Series I: Personal, 1847-1925Subseries I.1: Correspondence, 1857-1925