http://matome.naver.jp/odai/2136859473149571501

http://jukuyobiko.blogspot.jp/2016/01/blog-post.html

http://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q1111739701

http://www.ne.jp/asahi/cccp/camera/HoppouRyoudo/MAP_Kyoukasho/OtherMap/

http://www.yukihy.com/entry/Maxwell's4equations

http://blog.livedoor.jp/drazuli/archives/8590815.html

http://matome.naver.jp/odai/2141479398001948301

https://ja.wikipedia.org/wiki/%E3%83%93%E3%83%BC%E3%83%AD%E3%83%BC%E3%83%BB%E3%83%A9%E3%83%BC%E3%82%B9%E3%83%AD%E3%83%BC

http://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q109287365

http://gigazine.net/news/20161014-hubble-galaxies/http://gigazine.net/news/20161014-hubble-galaxies/