*1:See also https://sumita-m.hatenadiary.com/entry/2019/07/30/081016 https://sumita-m.hatenadiary.com/entry/2019/12/02/001041 https://sumita-m.hatenadiary.com/entry/2020/01/04/235902 https://sumita-m.hatenadiary.com/entry/2020/01/22/082357 https://sumita-m.hatenadiary.com/entry/2020/02/01/082715 https://sumita-m.hatenadiary.com/entry/2020/02/13/210049
