by Thomas W. Dibblee, Jr. ; edited by John A. Minch. Relief shown by contours and spot heights. "Topographic base map from available USGS 7.5-minute quadrangle Idria, CA 1969. DMA 1856 I NW - Series V895." "First printing, March 2007." "Frank Cressy honorary map." Includes quadrangle location map, index to adjacent 7.5 minute quadrangles, and index to sources of geology, most recent 1969. Includes "pertinent references", most recent 1972.