1John Jacob Astor to Thomas Jefferson, 14 March 1812 (Jefferson Papers)
Lewis and Clark Expedition; route of [index entry]
2Thomas Jefferson to Paul Allen, 18 August 1813 (Jefferson Papers)
Lewis and Clark Expedition; route of [index entry]
3Thomas Jefferson to John Adams, 8 April 1816 (Jefferson Papers)
Lewis and Clark Expedition; route of [index entry]
4Thomas Jefferson to Henry Dearborn, 27 October 1818 (Jefferson Papers)
Lewis and Clark Expedition; route of [index entry]