1Alexander von Humboldt to Thomas Jefferson, 12 June 1809 (Jefferson Papers)
Gay-Lussac, Joseph Louis [index entry]
2David Bailie Warden to Thomas Jefferson, 28 June 1809 (Jefferson Papers)
Gay-Lussac, Joseph Louis [index entry]
3David Bailie Warden to Thomas Jefferson, 2 January 1811 (Jefferson Papers)
Gay-Lussac, Joseph Louis [index entry]
4David Bailie Warden to Thomas Jefferson, 14 April 1811 (Jefferson Papers)
Gay-Lussac, Joseph Louis [index entry]