1Thomas Jefferson to William Clark, 8 September 1816 (Jefferson Papers)
Clark (Clarke), William; and papers of Lewis and Clark Expedition [index entry]
2William Clark to Thomas Jefferson, 10 October 1816 (Jefferson Papers)
Clark (Clarke), William; and papers of Lewis and Clark Expedition [index entry]
3Peter S. Du Ponceau to Thomas Jefferson, 5 December 1817 (Jefferson Papers)
Clark (Clarke), William; and papers of Lewis and Clark Expedition [index entry]
4Peter S. Du Ponceau to Thomas Jefferson, 14 February 1818 (Jefferson Papers)
Clark (Clarke), William; and papers of Lewis and Clark Expedition [index entry]
5Enclosure: Nicholas Biddle to William Tilghman, 6 April 1818 (Jefferson Papers)
Clark (Clarke), William; and papers of Lewis and Clark Expedition [index entry]
6Peter S. Du Ponceau to Thomas Jefferson, 14 April 1818 (Jefferson Papers)
Clark (Clarke), William; and papers of Lewis and Clark Expedition [index entry]