2020年9月21日。
永青文庫*1。文京区目白台1丁目*2。
*1:http://www.eiseibunko.com/ https://twitter.com/eiseibunko See eg. https://ja.wikipedia.org/wiki/%E6%B0%B8%E9%9D%92%E6%96%87%E5%BA%AB See also https://sumita-m.hatenadiary.com/entry/20150522/1432260975 https://sumita-m.hatenadiary.com/entry/20150713/1436798077
*2:See also https://sumita-m.hatenadiary.com/entry/20170602/1496329662 https://sumita-m.hatenadiary.com/entry/2021/09/06/085334