1William Thornton to Thomas Jefferson, 8 May 1812 (Jefferson Papers)
Catalogus Plantarum Americæ Septentrionalis (H. Muhlenberg) [index entry]
2Thomas Jefferson to Henry Muhlenberg, 16 March 1814 (Jefferson Papers)
Catalogus Plantarum Americæ Septentrionalis (H. Muhlenberg) [index entry]