1John Adams to Thomas Jefferson, 3 December 1813 (Jefferson Papers)
Diogenes Laertius; Lives of Eminent Philosophers (trans. R. D. Hicks) [index entry]
2John Adams to Thomas Jefferson, February–3 March 1814 (Jefferson Papers)
Diogenes Laertius; Lives of Eminent Philosophers (trans. R. D. Hicks) [index entry]