※ 자료 출처)
▶ 유튜브
https://www.youtube.com/watch?v=KwdN4RZP49Y
▶ KBS 다큐공감
https://vod.kbs.co.kr/index.html?source=episode&sname=vod&stype=vod&program_code=T2013-0126&program_id=PS-2018090243-01-000&broadcast_complete_yn=&local_station_code=00§ion_code=05