References
- 노동신문(2020.1.22.)
- 자연과학 - 초급중학교 2 (교육도서출판사, 2014)
- 지리 - 고급중학교 2 (교육도서출판사, 2014)
- 물리 - 고급중학교 2 (교육도서출판사, 2014)
- 북한학보(사단법인 북한연구소, 46집 2호, 2021)
- 우리나라의 자연보호지역(2005)
- https://www.rfa.org/korean/news_indepth/nkfloodsp-08102021224021.html
- https://www.joongang.co.kr/article/4695274#home
- https://www.tongilnews.com/news/articleView.html?idxno=203054
- https://www.voakorea.com/a/6205804.html
- https://www.voakorea.com/a/6205804.html
- https://nownews.seoul.co.kr/news/newsView.php?id=20220531601002&wlog_tag3=naver
- http://www.segye.com/newsView/20220524510604?OutUrl=naver
- http://www.cybernk.net
- https://www.unikorea.go.kr/nkhr/current/life/living/education/?boardId=bbs_0000000000000079&mode=view&cntId=53087&category=&pageIdx=