by Thomas W. Dibblee, Jr. ; edited by John A. Minch. Relief shown by contours and spot heights. "Topographic base map from newest available USGS 7.5-minute quadrangle CABAZON, CA 1956, AMS 2651 IV NE -- Series V895, PHOTOREVISED 1994." "First printing, August 2004." "Clarence Allen Honorary Map". Includes quadrangle location map, index to adjacent 7.5 minute quadrangles, and index to sources of geology. Includes "pertinent references."