1John Vaughan to Thomas Jefferson, 19 August 1809 (Jefferson Papers)
American Philosophical Society; librarian of [index entry]
2John Vaughan to Thomas Jefferson, 20 August 1809 (Jefferson Papers)
American Philosophical Society; librarian of [index entry]
3Thomas Jefferson to John Vaughan, 31 August 1809 (Jefferson Papers)
American Philosophical Society; librarian of [index entry]