http://news.goo.ne.jp/article/toyokeizai/business/toyokeizai-97503.html

http://gigazine.net/news/20151219-google-energy-kite/

http://www3.nhk.or.jp/news/html/20151218/k10010345541000.html

http://www.asahi.com/articles/ASHDL5FHCHDLUTIL04Y.html?platform=hootsuite

http://www.yomiuri.co.jp/national/20151219-OYT1T50145.html?from=ycont_top_txt