A survey of uranium concentrations in rocks and soils in populated areas of Arizona: Methods, in Spencer, J.E., ed., Radon in Arizona

Duncan, J.T., and Spencer, J.E., 1993, A survey of uranium concentrations in rocks and soils in populated areas of Arizona: Methods, in Spencer, J.E., ed., Radon in Arizona: Arizona Geological Survey Bulletin 199, p. 93-96.