Mozart, Wolfgang Amadeus : Arien, Sopran Kl Orch, KV 505
| Louis Spohr an Wilhelm Speyer in Frankfurt am Main | Kassel, Montag 10. September 1838 | 1838091002 |
| Wilhelm Speyer an Louis Spohr in Kassel | Frankfurt am Main, Montag 10. und Mittwoch 12. September 1838 | 1838091032 |
| Louis Spohr an Wilhelm Speyer in Frankfurt am Main | Kassel, Freitag 21. September 1838 | 1838092102 |
| Louis Spohr an Julius André in Frankfurt am Main | Kassel, Sonnabend 27. Oktober 1838 | 1838102726 |