1John Adams to Thomas Jefferson, 16 July 1814 (Jefferson Papers)
Chinese language; study of [index entry]
2Charles J. Ingersoll to Thomas Jefferson, 4 July 1818 (Jefferson Papers)
Chinese language; study of [index entry]
3Thomas Jefferson to Charles J. Ingersoll, 20 July 1818 (Jefferson Papers)
Chinese language; study of [index entry]