Sources: DFo
- Samuel L. Clemens to Charles E. Flower, 14 July 1873 · London, England · UCCL00952 DFo
- Samuel L. Clemens to Charles E. Flower, 27 October 1875 · Hartford, Conn · UCCL01276 DFo
- Samuel L. Clemens to Augustin Daly, per Telegraph Operator, 3 August 1877 · Elmira, N.Y · UCCL01462 DFo
- Samuel L. Clemens to Augustin Daly, 15 August 1877 · New York, N.Y · UCCL01471 DFo
- SLC per Unidentified to Chatto & Windus, 18 January 1882 · Hartford, Conn · UCCL11890 DFo
- SLC to Augustin Daly, 17 April 1887 · Hartford, Conn · UCCL11630 DFo
- SLC to Augustin Daly, 25 April 1887 · Hartford, Conn · UCCL11629 DFo
- SLC to Augustin Daly, 27 April 1887 · Hartford, Conn · UCCL09246 DFo
- SLC to Augustin Daly, 5 April 1888 · Hartford, Conn · UCCL03713 DFo
- SLC to Augustin Daly, 6 October 1888 · Hartford, Conn · UCCL03784 DFo
- SLC to Daniel Frohman, 27 October 1889 · Hartford, Conn · UCCL03958 DFo
- SLC to Daniel Frohman, 10 February 1890 · Hartford, Conn · UCCL04014 DFo
- SLC to William Winter, 28 April 1903 · Riverdale, N.Y · UCCL06639 DFo
- SLC to M. B. Colcord, 18 May 1909 · Redding, Conn · UCCL08397 DFo
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