||The Quaternary Geologic Map of the Chicago 4° x 6° Quadrangle was mapped as part of the Quaternary Geologic Atlas of the United States. The atlas was begun as an effort to depict the areal distribution of surficial geologic deposits and other materials
||Richmond, Gerald M.; U.S. Geological Survey; Fullerton, David S.; Lineback, Jerry A.; Bleuer, Ned K.; Mickelson, David M.; Farrand, William R.; and Goldthwait, Richard P.
||U.S. Geological Survey Miscellaneous Investigations Series Map I-1420 (NK-16)