Sources: NN
- Samuel L. Clemens to Charles F. Wingate, 31 March 1870 · Buffalo, N. Y · UCCL00451
- Samuel L. Clemens to Edward P. Ackerman, 31 July 1871 · Elmira, N.Y · UCCL00641
- Samuel L. Clemens to Horace Greeley, 17 August 1871 · Hartford, Conn · UCCL00645
- Samuel L. Clemens to Frank Mayo, 19–22 March 1872 · Elmira, N.Y · UCCL11847
- Samuel L. Clemens to Unidentified, 19 March–8 May 1872 · Elmira, N.Y · UCCL09046
- Samuel L. Clemens to Elisha Bliss, Jr., 28 July 1872 · New Saybrook, Conn · UCCL00781
- Samuel L. Clemens to James Redpath, 24 January 1873 · Hartford, Conn · UCCL00864
- Samuel L. Clemens to the Staff of the New York Tribune, 30 January 1873 · Hartford, Conn · UCCL00870
- SLC to Whitelaw Reid, 7 March 1873 · Hartford, Conn · UCCL00884
- Samuel L. Clemens to the Staff of the New York Tribune, 7 March 1873 · Hartford, Conn · UCCL00885
- Samuel L. Clemens to to Victor Wolff, per Fanny C. Hesse, 1? January 1877 · Hartford, Conn · UCCL10739
- SLC to James R. Osgood, 7 March–14 March 1883 · Hartford, Conn · UCCL08820
- SLC to Benjamin H. Ticknor, 7–14 March 1883 · Hartford, Conn · UCCL02329
- SLC to Unidentified, 15 April 1885 · Hartford, Conn · UCCL03217
- SLC to Karl Gerhardt, 8 October 1885 · Hartford, Conn · UCCL03293
- SLC to Pelham Ogle, 15 November 1885 · Hartford, Conn · UCCL03308
- SLC to Julian Hawthorne, 18 December 1885 · Hartford, Conn · UCCL03336
- SLC to Richard Watson Gilder, 11 March 1888 · New York, N.Y · UCCL03707
- SLC to Richard Watson Gilder, 30 July 1888, Elmira, N.Y · UCCL13371
- SLC to Robert U. Johnson, 6 September 1888 · Elmira, N.Y · UCCL03757
- SLC to Richard Watson Gilder, 21 February 1889 · Hartford, Conn · UCCL03866
- SLC to Abraham G. Mills, 23 March 1889 · Hartford, Conn · UCCL10740
- SLC to Abraham G. Mills, 27 March 1889 · Hartford, Conn · UCCL10741
- SLC to Abraham G. Mills, 4 April 1889 · Hartford, Conn · UCCL10742
- SLC to Abraham G. Mills, 15 April 1889 · Hartford, Conn · UCCL10743
- SLC to Richard Watson Gilder, 16 May 1889 · Hartford, Conn · UCCL03893
- SLC to Richard Watson Gilder, 5 October 1889 · Hartford, Conn · UCCL03945
- SLC to Richard R. Bowker, 9 October 1889 · Hartford, Conn · UCCL03949
- SLC to Richard R. Bowker, 2 December 1889 · Hartford, Conn · UCCL03981
- SLC to Andrew Carnegie, 17 March 1890 · Hartford, Conn · UCCL04027
- SLC to Andrew Carnegie, 23 April 1890 · Hartford, Conn · UCCL04043
- SLC to Andrew Carnegie, 1 May 1890 · Hartford, Conn · UCCL04044
- SLC to Andrew Carnegie, 19 May 1890 · New York, N.Y · UCCL08486
- SLC to Chauncey M. Depew, 30 August 1892 · Bad Nauheim, Germany · UCCL01878
- SLC to Andrew Carnegie, 7 April 1893 · New York, N.Y · UCCL04365
- SLC to Frank Mayo, 19 May 1895 · New York, N.Y · UCCL11889
- SLC to Poultney Bigelow, <i>per</i> Telegraph Operator, 19 May 1896 · Johannesburg, South Africa · UCCL13574
- SLC to Arthur E. Gilbert, 6 February 1898 · Vienna, Austria · UCCL05343
- SLC to Arthur E. Gilbert, 12 February 1898 · Vienna, Austria · UCCL05349
- SLC to Arthur E. Gilbert, 15 April 1898 · Vienna, Austria · UCCL05376
- SLC to Richard Watson Gilder, 2 February 1899 · Vienna, Austria · UCCL05542
- SLC to Chauncey M. Depew, 2 February 1899 · Vienna, Austria · UCCL05541
- SLC to Richard Watson Gilder, 14 March 1899 · Vienna, Austria · UCCL05562
- SLC to Henry H. Rogers, 27 September 1899 · Sanna, Sweden · UCCL05681
- SLC to Richard Watson Gilder, 16 October 1899 · London, England · UCCL05690
- SLC to Richard R. Bowker, 4 December 1899 · London, England · UCCL05716
- SLC to Paul Kester, 24 March 1900 · London, England · UCCL05782
- SLC to Paul Kester, 25 March 1900 · London, England · UCCL05784
- SLC to Margaret Carnegie, 28 May 1900 · London, England · UCCL05810
- SLC to Richard Watson Gilder, 30 November 1900 · New York, N.Y · UCCL05923
- SLC to Richard Watson Gilder, 11 December 1900 · New York, N.Y · UCCL05929
- SLC to Edward W. Ordway, 13 January 1901 · New York, N.Y · UCCL06982
- SLC to Edward W. Ordway, 3 February 1901 · New York, N.Y · UCCL05987
- SLC to Edward W. Ordway, 1 May 1901 · New York, N.Y · UCCL06049
- SLC to Horace N. Allen, 4 December 1901 · Riverdale, N.Y · UCCL06180
- SLC to Horace N. Allen, 30 December 1901 · Riverdale, N.Y · UCCL06200
- SLC to Horace N. Allen, 2 January 1902 · Riverdale, N.Y · UCCL06215
- SLC to Edward W. Ordway, 14 January 1902 · Riverdale, N.Y · UCCL06244
- SLC to Paul Kester, 19 June 1902 · Bronx, N.Y · UCCL10168
- SLC to Paul Kester, 24 June 1902 · York Harbor, Me · UCCL06380
- SLC to Paul Kester, 27 July 1902 · York Harbor, Me · UCCL06390
- SLC to Edward W. Ordway, 2 November 1902 · Riverdale, N.Y · UCCL06480
- SLC per Isabel V. Lyon to Richard Watson Gilder, 10 December 1902 · Riverdale, N.Y · UCCL06508
- SLC per Isabel V. Lyon to William D. Howells, 9 February 1903 · Riverdale, N.Y · UCCL06579
- SLC per Isabel V. Lyon to Paul Kester, 10 February 1903 · New York, N.Y · UCCL10169
- SLC per Isabel V. Lyon to Paul Kester, 14 February 1903 · Riverdale, N.Y · UCCL06582
- SLC per Isabel V. Lyon to Paul Kester, 26 February 1903 · Riverdale, N.Y · UCCL06586
- SLC to Paul Kester, 9 March 1903 · Riverdale, N.Y · UCCL06593
- SLC to Louise W. Carnegie, 31 March 1903 · Riverdale, N.Y · UCCL06612
- SLC to Richard Watson Gilder, 1 August 1903 · Elmira, N.Y · UCCL06717
- SLC to John Y. MacAlister, 21 March 1904 · Florence, Italy · UCCL06811
- SLC to Unidentified, 28 September 1904 · Unknown place · UCCL10789
- SLC to Andrew Carnegie, 3 November 1904 · New York, N.Y · UCCL06944
- SLC to Louise W. Carnegie, 1904, Florence, Italy · UCCL06776
- SLC to Elizabeth Jordan, 10 March 1905 · New York, N.Y · UCCL07015
- SLC per Isabel V. Lyon to Richard Watson Gilder, 1 June 1905 · Dublin, N.H · UCCL07054
- SLC to Richard Watson Gilder, 15 August 1905 · Norfolk, Conn · UCCL07110
- Isabel V. Lyon for SLC to Paul Kester, 18 September 1905 · Dublin, N.H · UCCL07139
- SLC to Richard Watson Gilder, 3 November 1905 · Boston, Mass · UCCL07194
- SLC to Louise W. Carnegie, 1905, New York, N.Y · UCCL06975
- SLC per Isabel V. Lyon to Richard R. Bowker, 4 February 1906 · New York, N.Y · UCCL07327
- SLC to Unidentified, 12 April 1906 · New York, N.Y · UCCL09247
- SLC to Elizabeth Jordan, 6 July 1906 · New York, N.Y · UCCL07473
- SLC per Isabel V. Lyon to Elizabeth Jordan, 30 July 1906 · Dublin, N.H · UCCL07484
- SLC to Andrew Carnegie and Louise W. Carnegie, 31 December 1906 · New York, N.Y · UCCL07604
- Jean Clemens to William Dutcher, 21 March 1907 · Katonah, N.Y · UCCL10745
- SLC to John S. Billings, 22 March 1907 · New York, N.Y · UCCL07677
- Jean Clemens to William Dutcher, 6 October 1907 · Katonah, N.Y · UCCL10746
- Jean Clemens to William Dutcher, 16 October 1907 · Katonah, N.Y · UCCL07854
- Jean Clemens to Alfred Wagstaff, 6 May 1908 · Greenwich, Conn · UCCL10744
- Jean Clemens to William Dutcher, 18 May 1908 · Greenwich, Conn · UCCL10747
- SLC to W. H. Watts, 15 August 1908 · Redding, Conn · UCCL08086
- SLC to Richard R. Bowker, 22 December 1908 · Redding, Conn · UCCL08186
- SLC to Elizabeth Jordan, 1 January 1909 · Redding, Conn · UCCL08194
- Jean Clemens to William Dutcher, 15 February 1909 · Babylon, N.Y · UCCL08348
- SLC to Elizabeth Jordan, 26 June 1909 · Redding, Conn · UCCL08427
- SLC to John Bigelow, 12 October 1909 · Redding, Conn · UCCL13474
- SLC to Joseph B. Gilder, 19 November 1909 · Redding, Conn · UCCL08496
- SLC per Albert Bigelow Paine to Paul Kester, 26 December–17 January 1910 · Redding, Conn · UCCL08543
- SLC to Richard Watson Gilder, 19 May n.y. · Unknown place · UCCL05053
- SLC to Richard Watson Gilder, Unknown date · Unknown place · UCCL04304
- SLC to Elizabeth Jordan, Unknown date, Redding, Conn · UCCL08195
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