米国の事業体の形態(Forms of business entities in the USA) https://senmon.biz/%e7%b1%b3%e5%9b%bd%e3%81%ae%e4%ba%8b%e6%a5%ad%e4%bd%93%e3%81%ae%e5%bd%a2%e6%85%8bforms-of-business-entities-in-the-usa/