1Peter S. Du Ponceau to Thomas Jefferson, 24 January 1818 (Jefferson Papers)
Trist, Nicholas Philip; and W. Byrd’sHistory of the Dividing Line [index entry]
2Thomas Jefferson to Peter S. Du Ponceau, 19 February 1818 (Jefferson Papers)
Trist, Nicholas Philip; and W. Byrd’sHistory of the Dividing Line [index entry]