Cite This Item
MLA
Illinois State Geological Survey, and Geological Survey (U.S.). Base map of Illinois. Urbana, Ill.: The Survey, 1924. Web. 29 Sep 2026. <https://ark-dc3dev.bpl.org/ark:/50959/rn301202h>.
APA
Illinois State Geological Survey, & Geological Survey (U.S.). (1924). Base map of Illinois [Map]. Retrieved from https://ark-dc3dev.bpl.org/ark:/50959/rn301202h
Chicago
Illinois State Geological Survey, and Geological Survey (U.S.). "Base map of Illinois." Map. Urbana, Ill.: The Survey, 1924. Digital Commonwealth, https://ark-dc3dev.bpl.org/ark:/50959/rn301202h (accessed September 29, 2026).
Wikipedia
{{cite web | title=Base map of Illinois | website=DigitalCommonwealth.org | date=1924 | url=https://ark-dc3dev.bpl.org/ark:/50959/rn301202h | accessdate=September 29, 2026}}