*1:See also https://sumita-m.hatenadiary.com/entry/2020/04/10/220658 https://sumita-m.hatenadiary.com/entry/2020/05/25/082501 https://sumita-m.hatenadiary.com/entry/2020/12/02/092713 https://sumita-m.hatenadiary.com/entry/2020/12/22/140750 https://sumita-m.hatenadiary.com/entry/2021/03/09/094435 https://sumita-m.hatenadiary.com/entry/2021/03/19/082111 https://sumita-m.hatenadiary.com/entry/2021/03/28/182729 https://sumita-m.hatenadiary.com/entry/2021/04/19/185510 https://sumita-m.hatenadiary.com/entry/2021/05/06/084544 https://sumita-m.hatenadiary.com/entry/2021/06/26/210650