1. Fan X, Wei Y, Yu H, Yao YM, Gu YQ (1992) Study of radon level and exposure dose in Shanxi province (in Chinese). Chin J Radiol Med Prot 12:175–181
2. UNSCEAR (2000) Sources and effects of ionizing radiation. In: UNSCEAR 2000 Report. United Sales Publication, New York, pp 83–156
3. Kobayashi S, Fujimoto K, Iwasaki T (1991) National wide survey of indoor radon concentration in Japan. In: Proceedings of the 3rd international symposium of the environment, pp 63–67
4. Iida T, Sone K, Ikebe Y (1990) Some problems on the measurement of radon concentrations by cup method. In: Proceedings of the 25th annual meeting of Japan Health Physics Society, Tsukuba, Japan
5. Doi M, Fujimoto K, Kobayashi S et al (1994) Spatial distribution of thoron and radon concentrations in the ambient air of a traditional Japanese wooden house. Health Phys 66:43–49