Sources: TxAu3
- Samuel L. Clemens to James Redpath and George L. Fall, 11 October 1871 · Hartford, Conn · UCCL00659 WU-MU, TxAu3
- Samuel L. Clemens to James Redpath and George L. Fall per Telegraph Operator, 8 December 1871 · Buffalo, N.Y · UCCL00687 TxAu3
- Samuel L. Clemens to Ira F. Hart, per Olivia L. Clemens, 12 January 1873 · Hartford, Conn · UCCL00855 TxAu3
- Samuel L. Clemens to James Redpath, 1 February 1874 · Hartford, Conn · UCCL01043 TxAu3
- Samuel L. Clemens to Cashier, First National Bank of Hartford, 04 February 1876 · Hartford, Conn · UCCL12995 TxAu3
- SLC to Unidentified, 17 April 1876 · Hartford, Conn · UCCL13785 TxAu3
- SLC to the American Publishing Co. · 17 April 1877 · Hartford, Conn · UCCL09794 TxAu3
- Samuel L. Clemens to Matthew H. Bartlett, October 1877 · 2nd of 2 · Hartford, Conn · UCCL11172 TxAu3
- Samuel L. Clemens to Andrew Chatto, 21 January 1878 · Hartford, Conn · UCCL02324 TxAu3
- Samuel L. Clemens to Joseph Blackburn Jones, 30 October 1879 · Hartford, Conn · UCCL12006 TxAu3
- SLC to Robert Chaffee Morgan, 14-27 1881 · Hartford or Branford, Conn · UCCL13650 TxAu3
- SLC to Karl and Hattie J. Gerhardt, 26 June 1881 · Branford, Conn · UCCL01978 TxAu3, NHC
- SLC to Benjamin H. Ticknor, 15 August 1881 · Elmira, N.Y · UCCL02007 TxAu3
- SLC to Andrew Chatto, 1 March 1883 · Hartford, Conn · UCCL12923 TxAu3
- Samuel L. Clemens to Henry (Harry) M. Clarke, 119 July 1883 · 2nd of 2 · Elmira, N.Y · UCCL13226 TxAu3
- Samuel L. Clemens to Henry (Harry) M. Clarke, 1–19 July 1883 · 1st of 2 · Elmira, N.Y · UCCL13225 TxAu3
- SLC to Joseph B. Gilder, 16 May 1886 · Hartford, Conn · UCCL11414 InFw2, TxAu3
- SLC to Walter Lee Brown, 14 June 1886 · Hartford, Conn · UCCL03409 TxAu3
- SLC to Editors of the Century Magazine, 14 August 1887 · Elmira, N.Y · UCCL12920 TxAu3
- SLC to Franklin G. Whitmore, 25 August 1888 · Elmira, N.Y · UCCL11428 CLjC, TxAu3
- SLC to Charles Calvin Ziegler, 14 April 1893 · Chicago, Ill · UCCL12661 TxAu3
- SLC to Jean Clemens, 12 January 1894 · New York, N.Y · UCCL03993 TxAu3
- SLC to OLC, 26 and 28 August 1896 · Guildford, England · UCCL05100 CU-MARK, TxAu3
- SLC to Chatto & Windus, 23 March 1897 · London, England · UCCL10866 TxAu3
- SLC to the American Publishing Company, 6 February 1898 · Vienna, Austria · UCCL13789 TxAu3
- SLC to Edmund W. Gosse, 6 July 1899 · London, England · UCCL05651 TxAu3
- SLC to Augustus T. Gurlitz, 5 January 1901 · New York, N.Y · UCCL12193 TxAu3
- SLC to Virginia F. Boyle, 6 January 1902 · Riverdale, N.Y · UCCL06221 Mn2, TxAu3
- SLC to William D. Howells, 11 August 1902 · York Harbor, Me · UCCL12922 TxAu3
- SLC to Gertrude Swain, 16 October 1902 · Riverdale, N.Y · UCCL06464 TxAu3
- SLC per IVL to Emily S. Hutchings, 14 November 1902 · Riverdale, N.Y · UCCL06487 Mo6, TxAu3
- SLC to Unidentified, 23 December 1902 · Riverdale, N.Y · UCCL13564 TxAu3
- SLC to Charles S. and Elisabeth N. Fairchild, 20 July 1904 · Lee, Mass · UCCL06891 ODa2, TxAu3
- SLC to Elias Cornelius Benedict, 15 September 1904 · New York, N.Y · UCCL12919 TxAu3
- SLC to Unidentified, 6 December 1905 · New York, N.Y · UCCL13786 TxAu3
- SLC Paula Lorch, 29–31 December 1905 · New York, N.Y · UCCL07281 NN-BGC, TxAu3
- SLC to The Printer’s Home, January 1906 · New York, N.Y · UCCL12408 TxAu3
- SLC to Georgya E. Holly, 2–4 January 1906, New York, N.Y · UCCL13986 TxAu3
- SLC to Clara L. Clemens, 12 March 1907 · New York, N.Y · UCCL07675 CU-MARK, TxAu3
- SLC to Evelyn Gifford, 28 June 1907 · Oxford, England · UCCL11825 TxAu3
- SLC to Unidentified, April 1908, Unknown place · UCCL14036 TxAu3
- SLC to Oscar Garett Wall, 8 November 1909 · Redding, Conn · UCCL13619 TxAu3
- SLC to Albert Bigelow Paine, 5 February–7 February 1910 · Hamilton, Bermuda · UCCL08555 TxAu3
- SLC to Unidentified, Unknown date · Unknown place · UCCL12463 TxAu3
- SLC to Unidentified, Unknown date · Unknown place · UCCL12400 TxAu3
- SLC to Richard Watson Gilder, unknown date, unknown place · UCCL13788 TxAu3
- SLC to Katie Leary, Unknown date · Unknown place · UCCL13790 TxAu3
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