1. UNESCO.: Recommendation concerning the Protection and Promotion of Museums and Collections, their Diversity and their Role in Society. (2015). https://www.j-muse.or.jp/02program/pdf/UNESCO_RECOMMENDATION_ENG.pdf. Accessed 15 July 2022
2. United Nations.: Education for sustainable development in the framework of the 2030 Agenda for Sustainable Development. (2017). https://digitallibrary.un.org/record/1318978, Accessed 15 July 2022
3. Ministry of Education.: Policy on UNESCO activities for 2020–2021 (Report). (2019). https://www.mext.go.jp/unesco/001/2019/1422386.htm. Accessed 15 July 2022
4. Ministry of Education.: Revised Courses of Study. (2017, 2018, 2019). https://www.mext.go.jp/a_menu/shotou/new-cs/1384661.htm. Accessed 15 July 2022
5. Atsushi, N..: A study on the schoolchildren's concept of historical time in their “community”. The New Geogr. 34(3), 31–44 (1986)