1. National Council on Radiation Protection and Measurements, Natural Background Radiation in the United States,1975
2. National Council on Radiation Protection and Measurements, Natural Background Radiation in the United States,1975
3. Radon in Buildings;Collé,1980
4. United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), Sources and Effects of Ionizing Radiation,1977
5. Natural Radioactivity Contamination Problems;Conference of Radiation Control Program Directors, Inc.,1978