1David Bailie Warden to Thomas Jefferson, 16 January 1811 (Jefferson Papers)
An Account of Expeditions to the Sources of the Mississippi (Z. M. Pike) [index entry]
2Alexander von Humboldt to Thomas Jefferson, 20 December 1811 (Jefferson Papers)
An Account of Expeditions to the Sources of the Mississippi (Z. M. Pike) [index entry]
3Pierre Samuel Du Pont de Nemours to Thomas Jefferson, 25 January 1812 (Jefferson Papers)
An Account of Expeditions to the Sources of the Mississippi (Z. M. Pike) [index entry]
4Thomas Jefferson to Samuel Pleasants, 11 August 1813 (Jefferson Papers)
An Account of Expeditions to the Sources of the Mississippi (Z. M. Pike) [index entry]
5Samuel Pleasants to Thomas Jefferson, 17 August 1813 (Jefferson Papers)
An Account of Expeditions to the Sources of the Mississippi (Z. M. Pike) [index entry]
6Thomas Jefferson to Alexander von Humboldt, 6 December 1813 (Jefferson Papers)
An Account of Expeditions to the Sources of the Mississippi (Z. M. Pike) [index entry]
7John Vaughan to Thomas Jefferson, 30 July 1817 (Jefferson Papers)
An Account of Expeditions to the Sources of the Mississippi (Z. M. Pike) [index entry]
8Thomas Jefferson to Mathew Carey, 21 June 1818 (Jefferson Papers)
An Account of Expeditions to the Sources of the Mississippi (Z. M. Pike) [index entry]
9Mathew Carey & Son to Thomas Jefferson, 27 June 1818 (Jefferson Papers)
An Account of Expeditions to the Sources of the Mississippi (Z. M. Pike) [index entry]
10James Wilkinson to Thomas Jefferson, 4 August 1818 (Jefferson Papers)
An Account of Expeditions to the Sources of the Mississippi (Z. M. Pike) [index entry]