*1:See also https://sumita-m.hatenadiary.com/entry/20161130/1480485070 https://sumita-m.hatenadiary.com/entry/2020/02/16/111831 https://sumita-m.hatenadiary.com/entry/2020/03/08/002025 https://sumita-m.hatenadiary.com/entry/2020/03/11/233303 https://sumita-m.hatenadiary.com/entry/2020/05/08/083247 https://sumita-m.hatenadiary.com/entry/2020/05/28/104715
