Analysis of information sources in references of the Wikipedia article "William Cheung" in English language version.
Last September in Cologne, West Germany, noted wing chun expert William Cheung was assaulted by a 24-year old wing chun student while conducting seminar. The man was a member of the Ving Tsun Athletic Association, headed by Leung Ting, a bitter wing chun rival of Cheung.
Lee found a sifu, or master, through a street-gang member called William Cheung, who took him to a wing chun school run by Ip Man, who had begun teaching the style in Hong Kong around 1950.