*1:See also https://sumita-m.hatenadiary.com/entry/20100318/1268931002 https://sumita-m.hatenadiary.com/entry/20181005/1538730662 https://sumita-m.hatenadiary.com/entry/2020/03/05/034456 https://sumita-m.hatenadiary.com/entry/2021/03/23/084420 https://sumita-m.hatenadiary.com/entry/2021/05/30/093637 https://sumita-m.hatenadiary.com/entry/2022/07/25/134235
