Bachelder, John B. (John Badger),  Bien, Julius,  Neumann, Louis E.,  and Endicott & Co. (New York, N.Y.).  "Map of the battlefield of Gettysburg, July 1st, 2nd, 3rd, 1863."  Map.  1876.  Norman B. Leventhal Map & Education Center,  https://collections.leventhalmap.org/search/commonwealth:q524n589j (accessed October 23, 2020).