1James Ronaldson to Thomas Jefferson, 5 March 1809 (Jefferson Papers)
du Pont de Nemours, Eleuthère Irénée; and merino sheep [index entry]
2Joseph Dougherty to Thomas Jefferson, 19 April 1809 (Jefferson Papers)
du Pont de Nemours, Eleuthère Irénée; and merino sheep [index entry]
3Thomas Jefferson to Eleuthère I. du Pont de Nemours, 30 April 1812 (Jefferson Papers)
du Pont de Nemours, Eleuthère Irénée; and merino sheep [index entry]
4Joseph Dougherty to Thomas Jefferson, 13 November 1812 (Jefferson Papers)
du Pont de Nemours, Eleuthère Irénée; and merino sheep [index entry]