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2. 2) Center for Cancer Control and Information Services, National Cancer Center: 〈http://ganjoho.jp/public/statistics/pub/statistics01.html〉, cited 19 August, 2015.
3. 3) Yodogawa Christian Hospital, “Palliative Care Manual,” 5th ed., Saishin Igakusha, Osaka, 2008.
4. 4) Takeda F., Pain Clinic, 1, 83-89 (1986).
5. 5) Ministry of Health, Labour and Welfare, 〈http://www.mhlw.go.jp/stf/houdou/0000051607.html〉, cited 19 August, 2015.