Iwanow, Nikolai Kusmitsch
| Elisabeth Filipowicz an Louis Spohr in Kassel | London, Dienstag 16. August 1836 | 1836081640 |
| Elisabeth Filipowicz an Louis Spohr in Kassel | London, Montag 24. September 1838 | 1838092440 |
| Elisabeth Filipowicz an Louis Spohr in Kassel | London, Dienstag 16. August 1836 | 1836081640 |
| Elisabeth Filipowicz an Louis Spohr in Kassel | London, Montag 24. September 1838 | 1838092440 |