2019年4月5日。
上野公園*1。
*1:See also https://sumita-m.hatenadiary.com/entry/20081117/1226913089 https://sumita-m.hatenadiary.com/entry/20100628/1277750059 https://sumita-m.hatenadiary.com/entry/20150722/1437535845 https://sumita-m.hatenadiary.com/entry/20160818/1471486768 https://sumita-m.hatenadiary.com/entry/2019/04/06/102306 https://sumita-m.hatenadiary.com/entry/2020/01/14/115748 https://sumita-m.hatenadiary.com/entry/2020/02/23/134205 https://sumita-m.hatenadiary.com/entry/2020/03/11/140158 https://sumita-m.hatenadiary.com/entry/2020/03/16/110419 https://sumita-m.hatenadiary.com/entry/2020/05/11/153851 https://sumita-m.hatenadiary.com/entry/2020/06/28/164710 https://sumita-m.hatenadiary.com/entry/2020/07/03/105520 https://sumita-m.hatenadiary.com/entry/2020/07/19/231713 https://sumita-m.hatenadiary.com/entry/2020/09/04/135646 https://sumita-m.hatenadiary.com/entry/2020/09/23/092212
