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2. United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), Sources and effects of ionizing radiation, Vol. I, United Nations Publications, New York, 2000.
3. International Commission on Radiological Protection (ICRP), Protection Against Radon-222 at Home and at Work, Annals of the ICRP 65, Pergamon Press, New York, 1994.
4. “Unattached” Fraction of Short-lived Rn Decay Products in Indoor and Outdoor Environments