Walker, Francis Amasa, United States. Census Office, and Julius Bien & Co. "Maps showing the range, and, within the range, the degree of cultivation of certain principal crops." Map. New York: Julius Bien, lith., [1874]. Norman B. Leventhal Map & Education Center, https://collections.leventhalmap.org/search/commonwealth:gb19h9904 (accessed April 24, 2024).