1Thomas Jefferson to Caspar Wistar, 31 March 1809 (Jefferson Papers)
American Philosophical Society; and C. Wistar [index entry]
2Thomas Jefferson to Caspar Wistar, 23 November 1814 (Jefferson Papers)
American Philosophical Society; and C. Wistar [index entry]
3John Vaughan to Thomas Jefferson, 9 January 1815 (Jefferson Papers)
American Philosophical Society; and C. Wistar [index entry]
4American Philosophical Society to Thomas Jefferson, 20 January 1815 (Jefferson Papers)
American Philosophical Society; and C. Wistar [index entry]
5Thomas Jefferson to Robert M. Patterson, 8 February 1815 (Jefferson Papers)
American Philosophical Society; and C. Wistar [index entry]
6Thomas Jefferson to John Vaughan, 8 February 1815 (Jefferson Papers)
American Philosophical Society; and C. Wistar [index entry]
7Caspar Wistar to Thomas Jefferson, 27 April 1815 (Jefferson Papers)
American Philosophical Society; and C. Wistar [index entry]
8Peter S. Du Ponceau to Thomas Jefferson, 22 January 1818 (Jefferson Papers)
American Philosophical Society; and C. Wistar [index entry]
9John Vaughan to Thomas Jefferson, 22 January 1818 (Jefferson Papers)
American Philosophical Society; and C. Wistar [index entry]
10Robert M. Patterson to Thomas Jefferson, 23 January 1818 (Jefferson Papers)
American Philosophical Society; and C. Wistar [index entry]