Gilbert, W.G., and Skotnicki, Steve, 1993, Geologic map of the west-central Gila Bend Mountains, Maricopa County, Arizona [Yellow Medicine Butte 7.5 min]: Arizona Geological Survey Open-File Report 93-05, 16 p., 1 sheet, scale 1:24,000. Location: Gila Bend Mts., Cortez Butte,