The University of Illinois Map Library requests the following acknowledgement be included when using this Historical Map: Map provided courtesy of the Map Library at the University of Illinois at Urbana-Champaign.; No Copyright - United States; http://rightsstatements.org/vocab/NoC-US/1.0/
Thomas, Cowperthwait & Co. (n.d.). A new map of the State of Illinois.. Thomas, Cowperthwait & Co. (Philadelphia), c1850.. https://digital.library.illinois.edu/items/a2ae0210-994e-0134-2096-0050569601ca-7 (map)