*1:See also https://sumita-m.hatenadiary.com/entry/20161015/1476517356 https://sumita-m.hatenadiary.com/entry/2020/05/04/084756 https://sumita-m.hatenadiary.com/entry/2020/07/08/212010 https://sumita-m.hatenadiary.com/entry/2020/09/04/144825 https://sumita-m.hatenadiary.com/entry/2020/09/23/085017 https://sumita-m.hatenadiary.com/entry/2021/02/01/013649 https://sumita-m.hatenadiary.com/entry/2021/02/19/232522 https://sumita-m.hatenadiary.com/entry/2021/03/19/210932 https://sumita-m.hatenadiary.com/entry/2021/03/28/205916 https://sumita-m.hatenadiary.com/entry/2021/06/04/022706 https://sumita-m.hatenadiary.com/entry/2021/06/15/075710