1Thomas Jefferson to John Laval, 11 April 1819 (Jefferson Papers)
Correspondance littéraire, philosophique et critique (F. M. Grimm) [index entry]
2Thomas Jefferson to John Laval, 3 May 1819 (Jefferson Papers)
Correspondance littéraire, philosophique et critique (F. M. Grimm) [index entry]
3Thomas Jefferson to John Laval, 4 June 1819 (Jefferson Papers)
Correspondance littéraire, philosophique et critique (F. M. Grimm) [index entry]
4Thomas Jefferson to John Laval, 5 July 1819 (Jefferson Papers)
Correspondance littéraire, philosophique et critique (F. M. Grimm) [index entry]