Oberthür, Charles : Floris von Namur
| Charles Oberthür an Louis Spohr in Kassel | Wiesbaden, Sonntag 11. August 1850 | 1850081143 |
| Louis Spohr an Charles Oberthür in Wiesbaden (erschlossen) | Kassel, Freitag 16. August 1850 | 1850081613 |
| Charles Oberthür an Louis Spohr in Kassel | Wiesbaden, Dienstag 20. August 1850 | 1850082043 |