*1:See also https://sumita-m.hatenadiary.com/entry/20160818/1471486768 https://sumita-m.hatenadiary.com/entry/20181005/1538730662 https://sumita-m.hatenadiary.com/entry/2020/04/16/215020 https://sumita-m.hatenadiary.com/entry/2020/12/27/192147 https://sumita-m.hatenadiary.com/entry/2021/09/11/141151
