https://www.britannica.com/art/hanamichi
https://www.sumofanmag.com/content/Issue_21/Tachi-ai.pdf
https://www.japantimes.co.jp/sports/2019/05/19/sumo/sumo-101-tachiai/#.XqOgHC-z28g
https://en.wikipedia.org/wiki/Tachi-ai
https://www.japantimes.co.jp/sports/2019/09/25/sumo/injuries-continue-impact-sumo-landscape/#.XqOmRS-z28g
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2945234/
Music
"Advanced Japanese Folk" by Audiotoolz
https://freemusicarchive.org/music/Audiotoolz/Progressive_Folk/02_-_audiotoolz_-_advanced_japanese_folk
Under creative commons license: https://creativecommons.org/licenses/by-nc-nd/3.0/