1William A. Burwell to Thomas Jefferson, 6 January 1820 (Jefferson Papers)
Burwell, William Armistead; and scientific instruments for University of Virginia [index entry]
2Ferdinand R. Hassler to Thomas Jefferson, 10 December 1819 (Jefferson Papers)
scientific instruments; for University of Virginia [index entry]
3Ferdinand R. Hassler to Thomas Jefferson, 5 January 1820 (Jefferson Papers)
scientific instruments; for University of Virginia [index entry]
4Thomas Jefferson to William A. Burwell, 25 December 1819 (Jefferson Papers)
Burwell, William Armistead; and scientific instruments for University of Virginia [index entry]
5Thomas Jefferson to Ferdinand R. Hassler, 25 December 1819 (Jefferson Papers)
scientific instruments; for University of Virginia [index entry]
6Thomas Jefferson to Rodolph Schaer, 4 April 1819 (Jefferson Papers)
scientific instruments; for University of Virginia [index entry]
7Rodolph Schaer to Thomas Jefferson, 25 March 1819 (Jefferson Papers)
scientific instruments; for University of Virginia [index entry]