Addressees: Fuller, Frank
- Samuel L. Clemens to Frank Fuller, 1 and 8 June 1867 · New York, N.Y · UCCL00136 CtHMTH
- Samuel L. Clemens to Frank Fuller, 7 June 1867 · New York, N.Y · UCCL00135 ViU
- Samuel L. Clemens to Frank Fuller, 7 August 1867 · Naples, Italy · UCCL00142 CtY-BR
- Samuel L. Clemens to Frank Fuller, 24 November 1867 · Washington, D.C · UCCL00158 NN5
- Samuel L. Clemens to Frank Fuller, 2 December 1867 · Washington, D.C · UCCL00167 PBL
- Samuel L. Clemens to Frank Fuller, 5 December 1867 · Washington, D.C · UCCL00170 CtY-BR
- Samuel L. Clemens to Frank Fuller, 13 December 1867 · Washington, D.C · UCCL00173 NN5
- Samuel L. Clemens to Frank Fuller, 12 May 1868 · San Francisco, Calif · UCCL02782
- Samuel L. Clemens to Frank Fuller, 15 August 1868 · Hartford, Conn · UCCL02744 CLjC
- Samuel L. Clemens to Frank Fuller, 24 September 1868 · St. Louis, Mo · UCCL02753 CLjC
- Samuel L. Clemens to Frank Fuller, 5–30 October 1868 · Hartford, Conn · UCCL09079 CLjC
- Samuel L. Clemens to Frank Fuller, 26 April 1870 · Buffalo, N. Y · UCCL00460 WU-MU
- Samuel L. Clemens to Frank Fuller, 21 May 1870 · Buffalo, N.Y · UCCL00466 CU-MARK, CLjC
- Samuel L. Clemens to Frank Fuller, 31 January 1874 · Hartford, Conn · UCCL01041 MoSW
- SLC to Frank Fuller, 20 March 1874 · Hartford, Conn · UCCL12794 CU-MARK
- Samuel L. Clemens to Frank Fuller, 8–10 July 1874 · Elmira, N.Y · UCCL01107 CU-MARK
- Samuel L. Clemens to Frank Fuller, 6 September 1874 · Elmira, N.Y · UCCL01124 WU-MU, CLjC
- SLC to Frank Fuller, 29 September 1874 · Hartford, Conn · UCCL12808 CU-MARK
- Samuel L. Clemens to Frank Fuller, 5 April 1878 · New York, N.Y · UCCL01552 MoSW
- Samuel L. Clemens to Frank Fuller, 20 August 1878 · Lucerne, Switzerland · UCCL02526 NN-BGC
- Samuel L. Clemens to Frank Fuller with a note to Thomas L. James, New York Postmaster, 18 November 1879· Hartford, Conn · UCCL01721 MoSW
- Samuel L. Clemens to Frank Fuller, 22 November 1879 · Hartford, Conn · UCCL01723 NFred, CLjC
- Samuel L. Clemens to Frank Fuller, 26 November 1879 · Hartford, Conn · UCCL01747 NN5
- Samuel L. Clemens to Frank Fuller, 5 December 1879 · Hartford, Conn · UCCL01733 CLjC
- Samuel L. Clemens to Frank Fuller, 19 December 1879 · Hartford, Conn · UCCL01742 CLjC
- Samuel L. Clemens to Frank Fuller, 18 February 1880 · Hartford, Conn · UCCL13039 Hald2
- Samuel L. Clemens to Frank Fuller, 24 February 1880 · Hartford, Conn · UCCL01762 CU-MARK
- Samuel L. Clemens to Frank Fuller, April? 1880 · Hartford, Conn · UCCL11987
- Samuel L. Clemens to Frank Fuller, 22 April 1880 · Hartford, Conn · UCCL01791 WU-MU
- Samuel L. Clemens to Frank Fuller, 2 October 1880 · Hartford, Conn · UCCL01835 MoSW
- Samuel L. Clemens to Frank Fuller per Telegraph Operator, 30 October 1880 · Hartford, Conn · UCCL01849 CLjC
- SLC to Frank Fuller, 14 March 1882 · Hartford, Conn · UCCL03740
- SLC to Frank Fuller, 5 July 1882 · Hartford, Conn · UCCL02231 WU-MU
- SLC to Frank Fuller, 18 October 1884 · Hartford, Conn · UCCL03009 WU-MU
- SLC to Frank Fuller, 28 September 1885 · Hartford, Conn · UCCL03291 ViU
- SLC to Frank Fuller, 11 November 1885 · Hartford, Conn · UCCL02622 NN-BGC
- SLC to Frank Fuller, 21 December 1886 · Hartford, Conn · UCCL03805 NjWoE
- SLC to Frank Fuller, 29 December 1888 · Hartford, Conn · UCCL03812 CCan2
- SLC to Frank Fuller, 5? March 1889 · Hartford, Conn · UCCL11430 CLjC
- SLC to Frank Fuller, 12 October 1889 · Hartford, Conn · UCCL03951 WU-MU
- SLC to Frank Fuller, 16 October 1889 · Hartford, Conn · UCCL02696 NN-BGC
- SLC to Frank Fuller, 1 February 1894 · New York, N.Y · UCCL04683 CtY-BR
- SLC to Frank Fuller, 13 February 1894 · New York, N.Y · UCCL07756 CU-MARK
- SLC to Frank Fuller, 18 February 1894 · New York, N.Y · UCCL04694 CSt
- SLC to Frank Fuller, 6 March 1894 · New York, N.Y · UCCL04707 WU-MU
- SLC to Frank Fuller, 5 March 1895 · New York, N.Y · UCCL04846 WU-MU
- SLC to Frank Fuller, 13 June 1895 · Elmira, N.Y · UCCL04890 ViU
- SLC to Frank Fuller, 6 July 1895 · Elmira, N.Y · UCCL04927 MB
- SLC to Frank Fuller, 4 August 1895 · Helena, Mont · UCCL04938 CtWep1
- SLC to Frank Fuller, 26 March 1897 · London, England · UCCL08844 CtHMTH
- SLC to Frank Fuller, 1 May 1897 · London, England · UCCL05210 CU-MARK
- SLC to Frank Fuller, 27 May 1897 · London, England · UCCL05216 WU-MU
- SLC to Frank Fuller, 2 June 1897 · London, England · UCCL10102 ViU
- SLC to Frank Fuller, 3 June 1897 · London, England · UCCL05223 WU-MU
- SLC to Frank Fuller, 2 July 1897 · London, England · UCCL05248 WU-MU
- SLC to Frank Fuller, August 1900 · London, England · UCCL10113 ViU
- SLC to Frank Fuller, 12 August 1900 · London, England · UCCL09787 ViU
- SLC to Frank Fuller, 18 June 1901 · New York, N.Y · UCCL06073 ViU
- SLC to Frank Fuller, 16 November 1901 · Riverdale, N.Y · UCCL08873 CtHMTH
- SLC to Frank Fuller, 4 December 1901 · Riverdale, N.Y · UCCL06181 WU-MU
- SLC to Frank Fuller, 10 February 1906 · New York, N.Y · UCCL07336 CU-MARK
- Isabel V. Lyon for SLC to Frank Fuller, 20 March 1906 · New York, N.Y · UCCL09910
- SLC to Frank Fuller, 1 February n.y. · Unknown place · UCCL10186
- SLC to Frank Fuller, 31 March n.y. · Unknown place · UCCL09871
- SLC to Frank Fuller, 2 July n.y. · Elmira, N.Y · UCCL09053 WU-MU
- SLC to Frank Fuller, Unknown date, Hartford, Conn · UCCL09674
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