都道府県 章 - SERP Analysis

https://ja.wikipedia.org/wiki/%25E9%2583%25BD%25E9%2581%2593%25E5%25BA%259C%25E7%259C%258C%25E7%25AB%25A0

https://uub.jp/prf/mark.html

https://www.nga.gr.jp/pref_info/symbol/

https://uub.jp/prf/kensho.html

https://www.city.murakami.lg.jp/uploaded/attachment/4571.pdf

http://www.fukaya-toyosato-j.ed.jp/%3Faction%3Dcommon_download_main%26upload_id%3D2628

https://www.bijutsushiryo.com/archives/8210

https://www.pinterest.com/pin/834151162229352828/

https://hiroseki.sakura.ne.jp/todoufuken.html