Sources: CCamarSJ
- Samuel L. Clemens to Emeline B. Beach, 5 December 1867 · Washington, D.C · UCCL00169
- Samuel L. Clemens to Emeline B. Beach, 8 January 1868 · Washington, D.C · UCCL00174
- SLC to OLC, 10–13 September 1869 · Unknown place · UCCL09405
- Samuel L. Clemens to Emeline B. Beach, 4 February 1874 · Hartford, Conn · UCCL01044
- SLC to OLC, 25 August 1881 · Boston, Mass · UCCL02015
- SLC to Susy (Olivia Susan) Clemens, 25 May 1882 · Hartford, Conn · UCCL09121
- SLC to OLC, 25 December 1885 · Hartford, Conn · UCCL10650
- SLC to Ulysses S. Grant, Jr., 1885, Unknown place · UCCL13347
- SLC to Rollin M. Daggett, 21 October 1886 · Hartford, Conn · UCCL03473
- SLC to Hartford City Government, 14 October 1888 · Hartford, Conn · UCCL08825
- SLC to Frederick J. Hall, 11 November 1889 · Hartford, Connecticut · UCCL13055
- SLC to Frederick J. Hall, 14 November 1889 · Hartford, Connecticut · UCCL13054
- SLC to Susan Corey, 25 December 1889 · Hartford, Conn · UCCL10640
- SLC to Daniel Frohman, 2 February 1890 · New York, N.Y · UCCL04010
- SLC to Unidentified, 27 November 1891 · Berlin, Germany · UCCL04257
- SLC to Mary Mapes Dodge, 31 October 1893 · New York, N.Y · UCCL04479
- SLC to James M. Tuohy, 2 November 1898 · Vienna, Austria · UCCL05458
- SLC to James M. Tuohy, 8 November 1898 · Vienna, Austria · UCCL05463
- SLC to James M. Tuohy, 10 November 1898 · Vienna, Austria · UCCL05465
- SLC to James M. Tuohy, 3 March 1899 · Vienna, Austria · UCCL05554
- SLC to James M. Tuohy, 22 March 1899 · Vienna, Austria · UCCL05567
- SLC to James M. Tuohy, 30 October 1899 · London, England · UCCL05697
- SLC to James M. Tuohy, 4 November 1899 · London, England · UCCL05699
- SLC to James M. Tuohy, 19 December 1899 · London, England · UCCL05719
- SLC to Unidentified, 28 April 1900 · London, England · UCCL08412
- SLC to OLC, 27 November 1901 · Riverdale, N.Y · UCCL10647
- SLC to OLC, 30 November 1901 · Riverdale, N.Y · UCCL10646
- SLC to Clara L. Clemens, Unknown date · Unknown place · UCCL10649
- SLC to Otis Skinner, 7 May 1906 · New York, N.Y · UCCL07438
- SLC to William E. Benjamin, Unknown date, New York, N.Y · UCCL08741
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