1Thomas Jefferson to John Vaughan, 9 April 1820 (Jefferson Papers)
Vaughan, John; and seal for University of Virginia [index entry]
2John Vaughan to Thomas Jefferson, 16 April 1820 (Jefferson Papers)
Vaughan, John; and seal for University of Virginia [index entry]
3Thomas Jefferson to John Vaughan, 24 April 1820 (Jefferson Papers)
Vaughan, John; and seal for University of Virginia [index entry]
4John Vaughan to Thomas Jefferson, 29 April 1820 (Jefferson Papers)
Vaughan, John; and seal for University of Virginia [index entry]