1997. Powell, Richard L., Frushour, Samuel S., Harper, Denver, and Kersey, Rea Williams. This map data was compiled in 1997 from information available at the time, but was unpublished until until 2002; the map does not reflect any chang... Indiana Geological Survey.
1968. Powell, Richard L. Blue line print. 'Base prepared from Bloomington, Clear Creek, Stanford and Whitehall topographic quadrangles, U.S.G.S, by the Indiana Geological S...
1967. Powell, Richard L. Includes 2 location maps. Scale approximately 1:380,000. Compiled by Richard L. Powell. Indiana Department of Geology and Natural Resources.