Beijing, Tianjin and Hebei's multimillion-yuan studies find smog is coming from neighbours
South China Morning Post, July 1, 2014
http://www.scmp.com/news/china/article/1544375/beijing-tianjin-and-hebeis-multimillion-yuan-studies-find-smog-coming
Night vision: China enlists drones in fight against pollution
中国出动无人机夜间抓拍排污企业
The Wall Street Journal, June 30, 2014
EN: http://blogs.wsj.com/chinarealtime/2014/06/30/night-vision-china-enlists-drones-in-fight-against-pollution/
CH: http://cn.wsj.com/gb/20140630/rec165933.asp