Johnson, D.H., 1963, Mineralogy and paragenesis of the ore deposit at the Monument No. 2 and Cato Sells mines, in Witkind, I.J., and Thaden, R.E., Geology and uranium-vanadium deposits of the Monument Valley area, Apache and Navajo Counties, Arizona: U.S. Geological Survey Bulletin 1103, p. 113-129.