1Peter S. Du Ponceau to Thomas Jefferson, 5 January 1818 (Jefferson Papers)
American Philosophical Society; Transactions [index entry]
2Peter S. Du Ponceau to Thomas Jefferson, 14 February 1818 (Jefferson Papers)
American Philosophical Society; Transactions [index entry]
3Thomas Jefferson to Silvain Godon, 21 May 1810 (Jefferson Papers)
American Philosophical Society; Transactions [index entry]
4Thomas Jefferson to Peter S. Du Ponceau, 7 November 1817 (Jefferson Papers)
American Philosophical Society; Transactions [index entry]
5Peter S. Du Ponceau to Thomas Jefferson, 22 January 1818 (Jefferson Papers)
American Philosophical Society; Transactions [index entry]
6Thomas Jefferson to George Hargraves, 29 August 1814 (Jefferson Papers)
American Philosophical Society; Transactions [index entry]
7Thomas Jefferson to John Vaughan, 28 June 1817 (Jefferson Papers)
American Philosophical Society; Transactions [index entry]
8William Lambert to Thomas Jefferson, 23 April 1812 (Jefferson Papers)
American Philosophical Society; Transactions [index entry]
9Thomas Jefferson to Caspar Wistar, 10 June 1817 (Jefferson Papers)
American Philosophical Society; Transactions [index entry]
10Enclosure: Alden Partridge’s Table of Altitudes of the Blue Ridge and Allegheny Mountains, [by 5 November 1810] (Jefferson Papers)
American Philosophical Society; Transactions [index entry]