1958. Wayne, William J.(William John), 1922-cartographer. Base modified from U.S. Geological Survey Base map of Indiana, 1953.; Reprinted with minor modifications, 1963. Scale 1:1,000,000. Indiana Geological Survey.
1970. Purcell, Roger L. Includes geological cross-section. Scale approximately 1:1,800,000. Adapted from Regional Geologic Map series, Indiana Geological Survey; drafted b... Indiana Geological Survey.
1956. Patton, John B.(John Barratt), 1915-cartographer. Base from Map of Indiana, 1950 edition, published by the U.S. Geological Survey. Minor revisions and additions made from Indiana Department of Cons... Indiana Geological Survey.