Sources: CtY
- Samuel L. Clemens to President of the Scroll and Key Society, 18 November 1868 · Cleveland, Ohio · UCCL02764 CtY
- Samuel L. Clemens to James Redpath, 10 May 1869 · Hartford, Conn · UCCL00298 CU-MARK, CtY
- John H. Riley to SLC, 16 May 1872 · Philadelphia, Pa. · UCLC31805 CtY
- William D. Howells to SLC, 13 November 1874 · Cambridge, Mass. · UCLC43490 CtY
- William D. Howells to SLC, 3 December 1874 · Cambridge, Mass. · UCLC32073 CtY
- Samuel L. Clemens to William D. Whitney, 16 January 1875 · Hartford, Conn · UCCL08610 CtY
- SLC to Elisha Bliss, Jr., 12 February–31 March 1875 · Hartford, Conn · UCCL11061 CtY
- Samuel L. Clemens to Elisha Bliss, Jr., 16? July 1875 · Hartford, Conn · UCCL01252 CtY
- William Wright to SLC, 21 November 1875 · Virginia City, Nev. · UCLC35597 CtY
- William Wright to SLC, 9 January 1876 · Virginia City, Nev. · UCLC35602 CtY
- William Wright to SLC, 16 April 1876 · Virginia City, Nev. · UCLC35606 CtY
- SLC to George A. Townsend, 26 February 1880 · Hartford, Conn · UCCL08598 CtY
- William A. Seaver to Samuel L. Clemens, 20 April 1880 · New York, N.Y. · UCLC32763 CtY
- SLC to Benjamin H. Ticknor, 9 September 1881 · Elmira, N.Y · UCCL02032 CtY
- SLC to Unidentified, 19 September 1881 · Elmira, N.Y · UCCL02040 CtY
- SLC to Henry B. Barnes, 25 January 1885 · Minneapolis, Minn · UCCL03133 CtY
- SLC to Karl Gerhardt, 11 July 1885 · Elmira, N.Y · UCCL03258 CtY
- SLC to Unidentified, 30 July 1885 · Elmira, N.Y · UCCL11047 CtY
- SLC to Annie E. Trumbull, 4 November 1885 · New York, N.Y · UCCL11018 CtY
- SLC to Benjamin H. Ticknor, 12 November 1885 · Hartford, Conn · UCCL03306 CtY
- SLC to Joseph H. Twichell and Harmony C. Twichell, 24 December 1885 · Hartford, Conn · UCCL03342 CtY
- SLC to ? Handy, 29 December 1885 · Hartford, Conn · UCCL03348 CtY
- SLC to Annie E. Trumbull, 4 May–5 May 1888 · Hartford, Conn · UCCL11037 CtY
- SLC per Franklin G. Whitmore to Francis E. Bliss, 9 October 1888 · Hartford, Conn · UCCL03787 ViU, CtY
- SLC to Unidentified, 10 April 1889 · Hartford, Conn · UCCL03882 CtY
- SLC to Unidentified, 30 April 1889 · Hartford, Conn · UCCL11046 CtY
- SLC to Edmund C. Stedman, 18 May 1889 · Hartford, Conn · UCCL03894 CtY
- SLC to Walt Whitman, 24 May 1889 · Hartford, Conn · UCCL03895 CtY
- SLC to Joseph T. Goodman, 19 November 1889 · Hartford, Conn · UCCL03970 CtY
- SLC to Joseph T. Goodman, 4 December 1889 · Hartford, Conn · UCCL03982 CtY
- SLC to L. E. Parkhurst, 20 December 1889 · Hartford, Conn · UCCL03991 CtY
- SLC to Joseph T. Goodman, 18 April 1890 · Hartford, Conn · UCCL04041 CtY
- SLC to Annie E. Trumbull, 28 April 1890 · Hartford, Conn · UCCL11019 CtY
- SLC to Annie E. Trumbull, 27 September 1890 · Hartford, Conn · UCCL10998 CtY
- SLC to Joseph T. Goodman, 23 October 1890 · Hartford, Conn · UCCL04105 CtY
- SLC to Annie E. Trumbull, 11 January 1891 · Hartford, Conn · UCCL11021 CtY
- SLC to Merriam (G.&C.) Co., 7 March 1891 · Hartford, Conn · UCCL04178 CtY
- SLC to John Horne, May 1891 · Hartford, Conn · UCCL09307 CtY
- SLC to Annie E. Trumbull, 31 May 1891 · Hartford, Conn · UCCL11020 CtY
- SLC to Annie E. Trumbull, 9 January 1892 · Ilsenburg, Germany · UCCL11022 CtY
- SLC, OLC to Annie E. Trumbull, 8 March 1892 · Menton, France · UCCL11023 CtY
- SLC to Joseph H. Twichell, 25 April 1892 · Rome, Italy · UCCL04285 CtY
- SLC to Sarah A. Trumbull, 18 July 1892 · Bad Nauheim, Germany · UCCL11017 CtY
- SLC to Francis E. Bliss, 31 October 1892 · Florence, Italy · UCCL08926 CtY
- SLC to Henry C. Robinson, 13 November 1892 · Florence, Italy · UCCL11049 CtY
- SLC to Henry C. Robinson, 20 July 1893 · Krankenheil, Germany · UCCL11050 CtY
- SLC to Annie E. Trumbull, 14 January 1894 · New York, N.Y · UCCL11031 CtY
- SLC to Frederick J. Hall, 31 March 1894 · Paris, France · UCCL04715 CtY
- SLC to Chatto & Windus, 2 July 1894 · La Bourboule, France · UCCL05251 CtY
- SLC to Henry C. Robinson, 23 July 1894 · New York, N.Y · UCCL11051 CtY
- SLC to Lloyd S. Bryce, 13 October 1894 · Rouen, France · UCCL04797 CtY
- SLC to Henry C. Robinson, 29 November 1894 · Paris, France · UCCL11053 CtY
- SLC to Francis E. Bliss, 9 December 1894 · Paris, France · UCCL04820 CtY
- SLC to Charles H. Webb, 16 February 1896 · Darjeeling, India · UCCL05021 CtY
- SLC to Henry C. Robinson, 4 July 1896 · Cape Town, Cape Colony · UCCL11052 CtY
- SLC to Annie E. Trumbull, 4 July 1896 · Cape Town, Cape Colony · UCCL11032 CtY
- SLC to American Publishing Co., 24 March 1897 · London, England · UCCL05189 CtY
- SLC to Joseph H. Twichell, 8 July 1897 · London, England · UCCL05258 CtY
- SLC to Francis E. Bliss, 28 August 1898 · Kaltenleutgeben, Austria · UCCL05424 CtY, WU-MU
- SLC to Henry M. Alden, 2 November 1898 · Vienna, Austria · UCCL05456 CtY
- SLC to Richard Watson Gilder, 6–13 November 1896 · Vienna, Austria · UCCL05459 CtY
- SLC to Joseph H. Twichell, 3 January 1899 · Vienna, Austria · UCCL05533 CtY
- Bertha Von Suttner for Comite fur Kundgebungen to SLC, May 1899 · Vienna, Austria · UCLC46236 CtY
- SLC to Joseph H. Twichell, May 1899 · Vienna, Austria · UCCL05599 CtY
- SLC to Joseph H. Twichell, 1 June 1899 · London, England · UCCL05637 CtY
- SLC to Joseph H. Twichell, 3 July 1899 · London, England · UCCL05647 CtY
- SLC to Unidentified, 3 August 1899 · Sanna, Sweden · UCCL11044 CtY
- SLC to Joseph H. Twichell, 6 September 1899 · Sanna, Sweden · UCCL05672 CtY
- SLC to Francis H. Skrine, 15 September 1899 · Sanna, Sweden · UCCL05676 CtY
- SLC to Harper & Brothers, 1 October 1899 · London, England · UCCL11064 CtY
- SLC to Unidentified, 8 November 1899 · London, England · UCCL11045 CtY
- SLC to Joseph H. Twichell, 21 November 1899 · London, England · UCCL05713 CtY
- SLC to Franklin G. Whitmore, 21 December 1899 · London, England · UCCL05721 CtY
- SLC to Francis E. Bliss, 25 April 1900 · London, England · UCCL11058 CtY
- SLC to Joseph H. Twichell, 18 August 1900 · London, England · UCCL05855 CtY
- SLC to John Brisben Walker, 27 September 1900 · London, England · UCCL05872 CtY
- SLC to Francis E. Bliss, 25 October 1900 · New York, N.Y · UCCL05885 CtY
- SLC to Thomas R. Lounsbury, 20 November 1900 · New York, N.Y · UCCL05915 CtY
- Augustus T. Gurlitz to SLC, 25 March 1901 · New York, N.Y. · UCLC33233 CtY
- SLC to William L. Phelps, 24 April 1901 · New York, N.Y · UCCL06044 CtY
- SLC to Joseph H. Twichell, 24 April 1901 · New York, N.Y · UCCL06046 CtY
- SLC to George B. Harvey, 4 May 1901 · New York, N.Y · UCCL06052 CtY
- George B. Harvey to SLC, 4 May 1901 · UCLC33266 CtY
- SLC per F. A. R. to Frank Parsons, 6 May 1901 · New York, N.Y · UCCL09119 CtY
- SLC to Francis E. Bliss, 14 May 1901 · New York, N.Y · UCCL06056 CtY
- Frank E. Bliss to SLC, 15 May 1901 · Hartford, Conn. · UCLC33267 CtY
- SLC to Francis E. Bliss, 20 May 1901 · New York, N.Y · UCCL11060 CtY
- SLC to Merriam (G.&C.) Co., 26 July 1901 · Saranac Lake, N.Y · UCCL06096 CtY
- SLC to Joseph H. Twichell, 29 September 1901 · New York, N.Y · UCCL06146 CtY
- SLC to Muriel M. Pears, 4 December 1901 · Riverdale, N.Y · UCCL06182 CtY
- SLC to Henry W. Fischer, 3 January 1902 · Riverdale, N.Y · UCCL06217 CtY
- SLC to Joseph H. Twichell, 4 January 1902 · Riverdale, N.Y · UCCL06220 CtY
- SLC to Muriel M. Pears, 14 February 1902 · Riverdale, N.Y · UCCL06276 CtY
- SLC to Francis E. Bliss, 15 February 1902 · Riverdale, N.Y · UCCL06278 CtY
- SLC to Muriel M. Pears, 21 June 1902 · Riverdale, N.Y · UCCL06372 CtY
- SLC to Joseph H. Twichell, 30 September 1902 · York Harbor, Me · UCCL06448 CtY
- SLC to Joseph H. Twichell, 31 December1902–1 January 1903 · Riverdale, N.Y · UCCL06534 CtY
- SLC to Joseph H. Twichell, 3–4 January 1903 · Riverdale, N.Y · UCCL06548 CtY
- SLC per Isabel V. Lyon to George B. Harvey, 12 January 1903 · Riverdale, N.Y · UCCL06556 CtY
- SLC to Muriel M. Pears, 14 January 1903 · Riverdale, N.Y · UCCL06560 CtY
- SLC to Joseph H. Twichell, 28 January 1903 · Riverdale, N.Y · UCCL06573 CtY
- Henry H. Rogers to SLC, 24 February 1903 · New York, N.Y. · UCLC33711 CtY
- SLC per Isabel V. Lyon to Francis E. Bliss, 25 February 1903 · Riverdale, N.Y · UCCL06585 CtY
- SLC to American Publishing Co., 28 April 1903 · Riverdale, N.Y · UCCL06635 CtY
- SLC to Francis E. Bliss, 11 May 1903 · Riverdale, N.Y · UCCL06655 CtY
- SLC to Annie E. Trumbull, 16 June 1903 · Riverdale, N.Y · UCCL11033 CtY
- SLC to Harriet E. Whitmore, 18 July 1903 · Elmira, N.Y · UCCL06702 CtY
- SLC to Joseph H. Twichell, 21 July 1903 · Elmira, N.Y · UCCL06704 CtY
- SLC to Francis E. Bliss, 29 July 1903 · Elmira, N.Y · UCCL06715 CtY
- Frank E. Bliss to SLC, 29 July 1903 · Hartford, Conn. · UCLC33808 CtY
- SLC to Joseph H. Twichell, 1 September 1903 · Elmira, N.Y · UCCL06722 CtY
- SLC, OLC to American Publishing Co., 23 October 1903 · New York, N.Y · UCCL06754 CtY
- SLC to Muriel M. Pears, 4 January 1904 · Florence, Italy · UCCL06781 CtY
- SLC to Muriel M. Pears, 9 May 1904 · Florence, Italy · UCCL06831 CtY
- SLC to Joseph H. Twichell, 8 June 1904 · Florence, Italy · UCCL06867 CtY
- SLC to Muriel M. Pears, 21 June 1904 · Florence, Italy · UCCL06848 CtY
- SLC to Thomas R. Lounsbury, 21 July 1904 · Lee, Mass · UCCL06896 CtY
- SLC to Joseph H. Twichell, 28 July 1904 · Lee, Mass · UCCL06906 CtY
- SLC to Joseph H. Twichell, 16 February 1905 · New York, N.Y · UCCL07001 CtY
- SLC to Muriel M. Pears, 18 February 1905 · New York, N.Y · UCCL07002 CtY
- SLC to Muriel M. Pears, 13 March 1905 · New York, N.Y · UCCL07017 CtY
- SLC to Joseph H. Twichell, 24 June 1905 · Dublin, N.H · UCCL07069 CtY
- SLC to Joseph H. Twichell, 13 July 1905 · Dublin, N.H · UCCL07082 CtY
- SLC to Muriel M. Pears, 26 July 1905 · Dublin, N.H · UCCL07090 CtY
- SLC to Muriel M. Pears, 11 October 1905 · Dublin, N.H · UCCL07172 CtY
- SLC to Joseph H. Twichell, 14 September 1906 · Dublin, N.H · UCCL07524 CtY
- Joseph H. Twichell to SLC, 14 September 1906 · UCLC35578 CtY
- SLC to Unidentified, Unknown date · Unknown place · UCCL11043 CtY
- SLC to Unidentified, Unknown date · Unknown place · UCCL11042 CtY
- SLC to Unidentified, Unknown date · Unknown place · UCCL11041 CtY
- SLC to Joseph H. Twichell, Unknown date · Unknown place · UCCL09020 CtY
1