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2. 2) M. Tsutsumi, K. Saito, S. Moriguchi, Spectrum-dose Conversion Operators, G(E) Functions of NaI(Tl) Scintillators Adapted for Effective Dose Equivalent Quantities, JAERI-M 91-204, [in Japanese].
3. 3) Japan Meteorological Agency, http://www.data.jma.go.jp/obd/stats/etrn/index.php, [in Japanese].
4. 4) Environmental radiation at High enrgy accelerator research organization, http://www.kek.jp/quake/radmonitor, [in Japanese].
5. 5) H. Matsumura, K. Saito, J. Ishioka et al., “Behavior of radioactive materials from Fukushima Daiichi Nuclear Power Station obtained by radiation scan on the expressways,” Trans. At. Energy Soc. Jpn., 10[3], to be published, [in Japanese].