Richard David Cushman recieved a Ph.D. in anthropology from Cornell University in 197?. His main work was with the Yao tribal people in northern Thailand, an ethnic group which is mainly located in south China. The Yao have a strong literary tradition, expressed in Chinese characters but in Yao language; their religious tradition is apparently something close to Taoism. One of Cushman's main preoccupations during field work in Thailand in the early 1970s was to collect Yao texts. He collected these by two main methods: 1) he hired older men to copy their religious texts into hardbacked notebooks; and 2) when he could obtain access to the original manuscripts, he photographed them. He also tape recorded Yao music and chanting on reel-to-reel audio tape.