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2. 2. Japanese Ministry of Health, Labour and Welfare. About the survey results regarding the status of public expenditure of pregnant women’s health checkups. Available at <https://www.mhlw.go.jp/file/04-Houdouhappyou-11908000-Koyoukintoujidoukateikyoku-Boshihokenka/H28kouhihutan_1.pdf>. Accessed February 7, 2020. Japanese.
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4. 4. National Institute of Infectious Diseases. Epidemiological information on rubella: as of January 29, 2020. Available at <https://www.niid.go.jp/niid/images/epi/rubella/2020/rubella200129.pdf>. Accessed February 7, 2020. Japanese.
5. 5. Japan Ministry of Health, Labour and Welfare. About additional measures against rubella. Available at <https://www.mhlw.go.jp/stf/seisakunitsuite/bunya/kenkou_iryou/kenkou/kekkaku-kansenshou/rubella/index_00001.html>. Accessed February 7, 2020. Japanese.