*1:See also https://sumita-m.hatenadiary.com/entry/20130408/1365437101 https://sumita-m.hatenadiary.com/entry/20140723/1406083089 https://sumita-m.hatenadiary.com/entry/20150724/1437745163 https://sumita-m.hatenadiary.com/entry/20150728/1438066833 https://sumita-m.hatenadiary.com/entry/20160817/1471400786 https://sumita-m.hatenadiary.com/entry/20170324/1490328369 https://sumita-m.hatenadiary.com/entry/2019/04/02/012302
