*1:See also https://sumita-m.hatenadiary.com/entry/2020/03/10/022606 https://sumita-m.hatenadiary.com/entry/2020/07/11/092525 https://sumita-m.hatenadiary.com/entry/2020/07/15/111420 https://sumita-m.hatenadiary.com/entry/2020/09/17/012308 https://sumita-m.hatenadiary.com/entry/2020/10/17/185518 https://sumita-m.hatenadiary.com/entry/2021/06/15/004301