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2. 2) The GHG Emissions Data of Japan (1990-2019): National GHG Inventory, https://www.nies.go.jp/gio/en/aboutghg/index.html, accessed on 24 May. 2021 (In Japanese)
3. 3) Transport Energy And CO2: International Energy Agency, 2009.
4. 4) Transport Energy Efficiency: International Energy Agency, 2010.
5. 5) Energy Efficiency 2020: International Energy Agency, 2020.