https://twitter.com/all_nations2/status/881312515531001856

https://science.srad.jp/story/17/07/06/0651214/

https://twitter.com/kerotto/status/886848652727033856

http://www.taro.org/2017/07/%E8%A2%AB%E7%81%BD%E5%9C%B0%E3%82%92%E9%A3%9F%E3%81%84%E7%89%A9%E3%81%AB%E3%81%99%E3%82%8B%E5%A5%B4%E3%82%89.php

http://blog.livedoor.jp/schulze/archives/52192128.html