Robert Fortune (2012). “A Journey to the Tea Countries of China: Including Sung-Lo and the Bohea Hills; with a Short Notice of the East India Company's Tea Plantations in the Himalaya Mountains”, p.329, Cambridge University Press
"High Price: A Neuroscientist's Journey of Self-Discovery That Challenges Everything You Know About Drugs and Society". Book by Carl Hart, June 11, 2013.
"Nato to take control in Libya after US, UK and France reach agreement" by Nicholas Watt, Nick Hopkins and Ian Traynor, www.theguardian.com. March 22, 2011.