*1:See also https://sumita-m.hatenadiary.com/entry/2020/06/24/111037 https://sumita-m.hatenadiary.com/entry/2020/09/08/080509 https://sumita-m.hatenadiary.com/entry/2020/10/08/112141 https://sumita-m.hatenadiary.com/entry/2020/10/12/030612 https://sumita-m.hatenadiary.com/entry/2021/06/06/073943 https://sumita-m.hatenadiary.com/entry/2021/07/15/082637