1William Lambert to Thomas Jefferson, 18 March 1822 (Jefferson Papers)
2Thomas Jefferson to William Lambert, 29 March 1822 (Jefferson Papers)
3Enclosure: William Lambert’s Methods of Calculating the Moon’s Parallaxes, 27–28 June 1822 (Jefferson Papers)
4Enclosure: William Lambert’s Calculation of the United States Capitol’s Longitude from Greenwich, 11 July 1822 (Jefferson Papers)