1Thomas Jefferson to Christopher Clark, 14 September 1815 (Jefferson Papers)
altitude; calculations for Peaks of Otter [index entry]
2Thomas Jefferson to Christopher Clark, 2 November 1815 (Jefferson Papers)
altitude; calculations for Peaks of Otter [index entry]
3Thomas Jefferson to Christopher Clark, 5 November 1815 (Jefferson Papers)
altitude; calculations for Peaks of Otter [index entry]