 During this project, Duff and Kew worked through the part-Tlingit interpreter for the Gitksan, Constance Cox.In 1958-59, while he was a professor of anthropology at the University of British Columbia, he worked alongside the anthropologist and folklorist Marius Barbeau in Ottawa on a Canada Council Senior Fellowship, organizing Barbeau and William Beynon's massive fieldnotes and other material on the Tsimshianic-speaking peoples (Tsimshian, Gitksan, and Nisga'a).Duff became a champion of the importance of the Barbeau-Beynon corpus, though he distanced himself from Barbeau's more controversial theories on the recent peopling of the Americas.