- SammlungDX19 - Cotton Family Papers
- SerieC - Francis Cotton : Family and general correspondence, personal papers : 66 to 133
- Family Correspondence
- Objekt81 - Letters from Rachel and Mary Cotton
- 1 - Letter : 29 September 1882
- 2 - Letter : 16 October 1882
- 3 - Letter : November 1882
- 4 - Letter : 27 November 1882
- 6 - Letter : 17 December 1882
- 7 - Letter : 26 December 1882
- 8 - Letter : 7 February 1883