Sources: CtWep1
- Samuel L. Clemens to Elisha Bliss, Jr., 5 July 1868 · San Francisco, Calif · UCCL02739
- Samuel L. Clemens to James N. Gillis, 26 January 1870 · Elmira, N.Y · UCCL00416
- Samuel L. Clemens to Elisha Bliss, Jr., 20 May 1870 · Buffalo, N.Y · UCCL00465
- Samuel L. Clemens to Elisha Bliss, Jr., 26 October 1870 · Buffalo, N.Y · UCCL00514
- Samuel L. Clemens to Elisha Bliss, Jr., 29 October 1870 · Buffalo, N.Y · UCCL00517
- Samuel L. Clemens to Elisha Bliss, Jr., 2 December 1870 · Buffalo, N.Y · UCCL00548
- Samuel L. Clemens to Elisha Bliss, Jr., 22 December 1870 · Buffalo, N.Y · UCCL02785
- Samuel L. Clemens to Elisha Bliss, Jr., 19 October 1871 · Wilkes-Barre, Pa · UCCL00665
- Samuel L. Clemens to Francis E. Bliss, 26 May 1872 · Elmira, N. Y · UCCL00753
- SLC to Unidentified, 21 June 1875 · Hartford, Conn · UCCL13244
- Samuel L. Clemens to Isaac White, 22 April 1876 · Hartford, Conn · UCCL07692
- Samuel L. Clemens to Elisha Bliss, Jr., 6 August 1877 · Elmira, N.Y · UCCL01465
- Samuel L. Clemens to Francis E. Bliss, 10 June 1879 · Paris, France · UCCL01665
- Samuel L. Clemens to Francis E. Bliss, 13 June 1879 · Paris, France · UCCL01668
- Samuel L. Clemens to Francis E. Bliss, 15 June 1879 · Paris, France · UCCL01670
- Samuel L. Clemens to Francis E. Bliss, 17 June 1879 · Paris, France · UCCL01671
- Samuel L. Clemens to Francis E. Bliss, 6 September 1879 · Elmira, N.Y · UCCL01683
- Samuel L. Clemens to Francis E. Bliss, 16 September 1879 · Elmira, N.Y · UCCL01691
- Samuel L. Clemens to Francis E. Bliss, 8 May 1880 · Hartford, Conn · UCCL01801
- SLC to Edith Beecher, March 1885 · Unknown place · UCCL12441
- SLC to William Winter, 5 November 1890 · Hartford, Conn · UCCL08604
- SLC to Frank Fuller, 4 August 1895 · Helena, Mont · UCCL04938
- SLC to Richard Watson Gilder, 12 March 1896 · Jaipur, India · UCCL05031
- SLC to Francis E. Bliss, 2 July 1897 · London, England · UCCL05249
- SLC to Francis E. Bliss, 11 February 1898 · Vienna, Austria · UCCL05348
- SLC to Francis E. (Frank) Bliss, May 1898 · Vienna or Kaltenleutgeben, Austria · UCCL05380
- SLC to James B. Pond, 17 June 1898 · Kaltenleutgeben, Austria · UCCL05401
- SLC to James M. Tuohy, 2 November 1898 · Vienna, Austria · UCCL05458
- 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 Francis E. Bliss, August 1902 · York Harbor, Me · UCCL06396
- SLC to Mai H. Coe, 25 December 1906 · New York, N.Y · UCCL13142
- SLC to Edith Thompson, 21 April 1908 · New York, N.Y · UCCL13611
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