艾未未促中国公民克服恐惧建立勇气社会 (Ai Weiwei in U.S. Press Urges Chinese Citizens to Overcome Fear, Establish Brave Society) Voice of America, April 28, 2013 http://www.voachinese.com/content/ai-weiwei-calls-for-courage-to-fight-tyrannys-20130428/1650281.html