Sources: NjNH2
- SLC to G. K. Jewett, 12 October 1871 · Hartford, Conn · UCCL12952 NjNH2
- Samuel L. Clemens to Olivia L. Clemens, 15 September 1872 · London, England · UCCL00807 NjNH2
- Samuel L. Clemens to Andrew Chatto, 28 April 1877 · Baltimore, Md · UCCL12932 NjNH2
- Samuel L. Clemens to Elisha Bliss, Jr., 6 March 1879 · Paris, France · UCCL11673 NjNH2
- SLC to Karl and Hattie J. Gerhardt, 21 November 1881 · Hartford, Conn · UCCL02094 NjNH2
- SLC to Horace Russell, 16 November 1882 · Hartford, Conn · UCCL02306 NjNH2
- SLC to Unidentified, 25 December 25 December 1889? · Hartford, Connecticut · UCCL13048 NjNH2
- SLC to Henry M. Alden, 30 April 1891 · Hartford, Conn · UCCL12940 NjNH2
- SLC to Richard Watson Gilder, 21 July 1891 · Aix-les-Bains, France · UCCL12410 NjNH2
- SLC to Frederick J. Hall, 2 December 1892 · Florence, Italy · UCCL00786 NjNH2
- SLC to Joseph Medill, 15 April 1893 · Chicago, Illinois · UCCL13046 NjNH2
- SLC to Unidentified, 6 September 1893 · At sea · UCCL13047 NjNH2
- SLC to John Y. MacAlister, 2 June 1899 · London, England · UCCL05630 NjNH2
- SLC to Elizabeth Jarrett, 9 May 1901 · New York, N.Y · UCCL13013 NjNH2
- SLC to Elizabeth Jarrett, ?5 May 1901 · New York, N. Y · UCCL11433 NjNH2
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