1. Aldrich, L.K., Sasser, M.K. and Conners, D.A. 1975. Evaluation of radon concentrations in North Carolina ground water supplies. North Carolina Department of Human Resources, Raleigh, NC.
2. Andrews, J.N. and Wood, D.F. 1972. Mechanism of radon release in rock matrices and entry into groundwaters.Institute of Mining andMetallurgyTransactions Sect.B.
81, No.792, B198–209.
3. Asikainen, M. and Kahlos, H. 1979. Anomalously high concentration of uranium, radium, and radon in water from drilled wells in the Helsinki region.Geochimica et Cosmochimica Acta,43, 1681–1686.
4. Baretto, P.M.C., Clark, R.B. and Adams, J.A.S. 1972. Physical characteristics of Rn-222 emanation from rocks, soil and minerals: Its relation to temperature and alpha dose.In Adams, J.A.S., Lowder, W.M. and Gesell, T.F., (Eds.),Natural Radiation Environment II, pp.731–738.
5. Bratsaert, W.F., Norton, S.A., Hess, C.T. and Williams, J.S. 1981. Geologic and hydrologic factors controlling radon-222 in groundwater in Maine.Ground Water,19, 407–417.