“Memorandum Books, 1786,” Founders Online, National Archives, https://founders.archives.gov/documents/Jefferson/02-01-02-0020. [Original source: The Papers of Thomas Jefferson, Second Series, Jefferson’s Memorandum Books, vol. 1, ed. James A Bear, Jr. and Lucia C. Stanton. Princeton: Princeton University Press, 1997, pp. 605–649.]
