* "Improvement in Machines for Reaping Small Grain": Cyrus H. McCormick, June 21, 1834* Farm Equipment on Antique Farming web site* McCormick Family Financial Records at Newberry Library
== External links ==* "Improvement in Machines for Reaping Small Grain": Cyrus H. McCormick, June 21, 1834* Farm Equipment on Antique Farming web site* McCormick Family Financial Records at Newberry Library