Sources: NN
- Samuel L. Clemens to Charles F. Wingate, 31 March 1870 · Buffalo, N. Y · UCCL00451 NN
- Samuel L. Clemens to Edward P. Ackerman, 31 July 1871 · Elmira, N.Y · UCCL00641 NN
- Samuel L. Clemens to Horace Greeley, 17 August 1871 · Hartford, Conn · UCCL00645 NN
- Samuel L. Clemens to Frank Mayo, 19–22 March 1872 · Elmira, N.Y · UCCL11847 NN
- Samuel L. Clemens to Unidentified, 19 March–8 May 1872 · Elmira, N.Y · UCCL09046 NN
- Samuel L. Clemens to Elisha Bliss, Jr., 28 July 1872 · New Saybrook, Conn · UCCL00781 NN
- Samuel L. Clemens to James Redpath, 24 January 1873 · Hartford, Conn · UCCL00864 NN
- Samuel L. Clemens to the Staff of the New York Tribune, 30 January 1873 · Hartford, Conn · UCCL00870 NN
- SLC to Whitelaw Reid, 7 March 1873 · Hartford, Conn · UCCL00884 NN
- Samuel L. Clemens to the Staff of the New York Tribune, 7 March 1873 · Hartford, Conn · UCCL00885 NN
- Samuel L. Clemens to to Victor Wolff, per Fanny C. Hesse, 1? January 1877 · Hartford, Conn · UCCL10739 NN
- SLC to James R. Osgood, 7 March–14 March 1883 · Hartford, Conn · UCCL08820 NN
- SLC to Benjamin H. Ticknor, 7–14 March 1883 · Hartford, Conn · UCCL02329 NN
- George W. Cable to SLC, 10 March 1883 · UCLC41494 NN
- SLC to Unidentified, 15 April 1885 · Hartford, Conn · UCCL03217 NN
- SLC to Karl Gerhardt, 8 October 1885 · Hartford, Conn · UCCL03293 NN
- SLC to Pelham Ogle, 15 November 1885 · Hartford, Conn · UCCL03308 NN
- SLC to Julian Hawthorne, 18 December 1885 · Hartford, Conn · UCCL03336 NN
- SLC to Richard Watson Gilder, 11 March 1888 · New York, N.Y · UCCL03707 NN
- SLC to Richard Watson Gilder, 30 July 1888, Elmira, N.Y · UCCL13371 NN
- SLC to Robert U. Johnson, 6 September 1888 · Elmira, N.Y · UCCL03757 NN
- SLC to Richard Watson Gilder, 21 February 1889 · Hartford, Conn · UCCL03866 NN
- SLC to Abraham G. Mills, 23 March 1889 · Hartford, Conn · UCCL10740 NN
- SLC to Abraham G. Mills, 27 March 1889 · Hartford, Conn · UCCL10741 NN
- SLC to Abraham G. Mills, 4 April 1889 · Hartford, Conn · UCCL10742 NN
- SLC to Abraham G. Mills, 15 April 1889 · Hartford, Conn · UCCL10743 NN
- SLC to Richard Watson Gilder, 16 May 1889 · Hartford, Conn · UCCL03893 NN
- SLC to Richard Watson Gilder, 5 October 1889 · Hartford, Conn · UCCL03945 NN
- Richard W. Gilder to SLC, 8 October 1889 · New York, N.Y. · UCLC44701 NN
- SLC to Richard R. Bowker, 9 October 1889 · Hartford, Conn · UCCL03949 NN
- SLC to Richard R. Bowker, 2 December 1889 · Hartford, Conn · UCCL03981 NN
- SLC to Andrew Carnegie, 17 March 1890 · Hartford, Conn · UCCL04027 NN
- SLC to Andrew Carnegie, 23 April 1890 · Hartford, Conn · UCCL04043 NN
- SLC to Andrew Carnegie, 1 May 1890 · Hartford, Conn · UCCL04044 NN
- SLC to Andrew Carnegie, 19 May 1890 · New York, N.Y · UCCL08486 NN
- SLC to Chauncey M. Depew, 30 August 1892 · Bad Nauheim, Germany · UCCL01878 NN
- SLC to Andrew Carnegie, 7 April 1893 · New York, N.Y · UCCL04365 NN
- SLC to Frank Mayo, 19 May 1895 · New York, N.Y · UCCL11889 NN
- SLC to Poultney Bigelow, <i>per</i> Telegraph Operator, 19 May 1896 · Johannesburg, South African Republic · UCCL13574 NN
- SLC to Arthur E. Gilbert, 6 February 1898 · Vienna, Austria · UCCL05343 NN
- SLC to Arthur E. Gilbert, 12 February 1898 · Vienna, Austria · UCCL05349 NN
- SLC to Arthur E. Gilbert, 15 April 1898 · Vienna, Austria · UCCL05376 NN
- SLC to Richard Watson Gilder, 2 February 1899 · Vienna, Austria · UCCL05542 NN
- SLC to Chauncey M. Depew, 2 February 1899 · Vienna, Austria · UCCL05541 NN
- Richard W. Gilder to SLC, 18 February 1899 · UCLC46223 NN
- SLC to Richard Watson Gilder, 14 March 1899 · Vienna, Austria · UCCL05562 NN
- SLC to Henry H. Rogers, 27 September 1899 · Sanna, Sweden · UCCL05681 NN
- SLC to Richard Watson Gilder, 16 October 1899 · London, England · UCCL05690 NN
- SLC to Richard R. Bowker, 4 December 1899 · London, England · UCCL05716 NN
- William D. Howells to SLC, 13 March 1900 · New York, N.Y. · UCLC32937 NN
- SLC to Paul Kester, 24 March 1900 · London, England · UCCL05782 NN
- SLC to Paul Kester, 25 March 1900 · London, England · UCCL05784 NN
- SLC to Margaret Carnegie, 28 May 1900 · London, England · UCCL05810 NN
- SLC to Richard Watson Gilder, 30 November 1900 · New York, N.Y · UCCL05923 NN
- SLC to Richard Watson Gilder, 11 December 1900 · New York, N.Y · UCCL05929 NN
- SLC to Edward W. Ordway, 13 January 1901 · New York, N.Y · UCCL06982 NN
- SLC to Edward W. Ordway, 3 February 1901 · New York, N.Y · UCCL05987 NN
- SLC to Edward W. Ordway, 1 May 1901 · New York, N.Y · UCCL06049 NN
- SLC to Horace N. Allen, 4 December 1901 · Riverdale, N.Y · UCCL06180 NN
- SLC to Horace N. Allen, 30 December 1901 · Riverdale, N.Y · UCCL06200 NN
- SLC to Horace N. Allen, 2 January 1902 · Riverdale, N.Y · UCCL06215 NN
- SLC to Edward W. Ordway, 14 January 1902 · Riverdale, N.Y · UCCL06244 NN
- SLC to Paul Kester, 19 June 1902 · Bronx, N.Y · UCCL10168 NN
- SLC to Paul Kester, 24 June 1902 · York Harbor, Me · UCCL06380 NN
- SLC to Paul Kester, 27 July 1902 · York Harbor, Me · UCCL06390 NN
- SLC to Edward W. Ordway, 2 November 1902 · Riverdale, N.Y · UCCL06480 NN
- Richard W. Gilder to SLC, 5 December 1902 · UCLC34862 NN
- SLC per Isabel V. Lyon to Richard Watson Gilder, 10 December 1902 · Riverdale, N.Y · UCCL06508 NN
- SLC per Isabel V. Lyon to William D. Howells, 9 February 1903 · Riverdale, N.Y · UCCL06579 NN
- SLC per Isabel V. Lyon to Paul Kester, 10 February 1903 · New York, N.Y · UCCL10169 NN
- SLC per Isabel V. Lyon to Paul Kester, 14 February 1903 · Riverdale, N.Y · UCCL06582 NN
- SLC per Isabel V. Lyon to Paul Kester, 26 February 1903 · Riverdale, N.Y · UCCL06586 NN
- SLC to Paul Kester, 9 March 1903 · Riverdale, N.Y · UCCL06593 NN
- SLC to Louise W. Carnegie, 31 March 1903 · Riverdale, N.Y · UCCL06612 NN
- SLC to Richard Watson Gilder, 1 August 1903 · Elmira, N.Y · UCCL06717 NN
- Richard W. Gilder to SLC, 4 August 1903 · New York, N.Y. · UCLC33810 NN
- SLC to John Y. MacAlister, 21 March 1904 · Florence, Italy · UCCL06811 NN
- SLC to Unidentified, 28 September 1904 · Unknown place · UCCL10789 NN
- SLC to Andrew Carnegie, 3 November 1904 · New York, N.Y · UCCL06944 NN
- SLC to Louise W. Carnegie, 1904, Florence, Italy · UCCL06776 NN
- SLC to Elizabeth Jordan, 10 March 1905 · New York, N.Y · UCCL07015 NN
- SLC per Isabel V. Lyon to Richard Watson Gilder, 1 June 1905 · Dublin, N.H · UCCL07054 NN
- SLC to Richard Watson Gilder, 15 August 1905 · Norfolk, Conn · UCCL07110 NN
- Isabel V. Lyon for SLC to Paul Kester, 18 September 1905 · Dublin, N.H · UCCL07139 NN
- Richard W. Gilder to SLC, 22 September 1905 · UCLC34649 NN
- SLC to Richard Watson Gilder, 3 November 1905 · Boston, Mass · UCCL07194 NN
- SLC to Louise W. Carnegie, 1905, New York, N.Y · UCCL06975 NN
- SLC per Isabel V. Lyon to Richard R. Bowker, 4 February 1906 · New York, N.Y · UCCL07327 NN
- SLC to Unidentified, 12 April 1906 · New York, N.Y · UCCL09247 NN
- SLC to Elizabeth Jordan, 6 July 1906 · New York, N.Y · UCCL07473 NN
- SLC per Isabel V. Lyon to Elizabeth Jordan, 30 July 1906 · Dublin, N.H · UCCL07484 NN
- SLC to Andrew Carnegie and Louise W. Carnegie, 31 December 1906 · New York, N.Y · UCCL07604 NN
- SLC to John S. Billings, 22 March 1907 · New York, N.Y · UCCL07677 NN
- Richard W. Gilder to SLC, 28 April 1908 · UCLC37778 NN
- SLC to W. H. Watts, 15 August 1908 · Redding, Conn · UCCL08086 NN
- SLC to Richard R. Bowker, 22 December 1908 · Redding, Conn · UCCL08186 NN
- SLC to Elizabeth Jordan, 1 January 1909 · Redding, Conn · UCCL08194 NN
- SLC to Elizabeth Jordan, 26 June 1909 · Redding, Conn · UCCL08427 NN
- John Bigelow to SLC, 11 October 1909 · Highland Falls, N.Y. · UCLC50623 NN
- SLC to John Bigelow, 12 October 1909 · Redding, Conn · UCCL13474 NN
- SLC to Joseph B. Gilder, 19 November 1909 · Redding, Conn · UCCL08496 NN
- SLC per Albert Bigelow Paine to Paul Kester, 26 December–17 January 1910 · Redding, Conn · UCCL08543 NN
- SLC to Richard Watson Gilder, 19 May n.y. · Unknown place · UCCL05053 NN
- SLC to Richard Watson Gilder, Unknown date · Unknown place · UCCL04304 NN
- SLC to Elizabeth Jordan, Unknown date, Redding, Conn · UCCL08195 NN
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