Sophienakademie <Prag>
| Wilhelm Happ an Louis Spohr in Kassel | Prag, Dienstag 13. April 1841 | 1841041340 |
| Wilhelm Happ an Louis Spohr in Kassel | Prag, Dienstag 13. April 1841 | 1841041340 |
| Wilhelm Happ an Louis Spohr in Kassel | Prag, Dienstag 13. April 1841 | 1841041340 |
| Wilhelm Happ an Louis Spohr in Kassel | Prag, Dienstag 13. April 1841 | 1841041340 |