1972. Gray, Henry Hamilton,1922-cartographer., Forsyth, Jane L. (Jane Louise),1921-cartographer., Schneider, Allan F. (Allan Frank),1926-cartographer., and Gooding, Ansel Miller. Base map modified from Army Map Service, Map NJ 16-3, 1964.' Includes text, cross section, columnar section, diagram, schematic section, ancillary ... Indiana Geological Survey.
1977. Bower, C. W. Date 2-10-66.' Indexed for points of interest. Scale not given. Dwg. by C.W. Bower; courtesy of Indiana & Michigan Electric Co.