*1:See also https://sumita-m.hatenadiary.com/entry/20160905/1473001572 https://sumita-m.hatenadiary.com/entry/2020/02/15/083534 https://sumita-m.hatenadiary.com/entry/2020/02/18/012709 https://sumita-m.hatenadiary.com/entry/2020/02/20/214335 https://sumita-m.hatenadiary.com/entry/2020/04/02/095218 https://sumita-m.hatenadiary.com/entry/2020/09/02/221828 https://sumita-m.hatenadiary.com/entry/2020/10/12/161525 https://sumita-m.hatenadiary.com/entry/2021/04/30/093327 https://sumita-m.hatenadiary.com/entry/2021/05/02/094430 https://sumita-m.hatenadiary.com/entry/2021/05/13/000055 https://sumita-m.hatenadiary.com/entry/2021/06/08/073934