Ernest Roland Duncan (25 January 1916 – November 25, 1990) was a New Zealand-born mathematician, Australian headmaster and American professor.Duncan was born in Clyde, New Zealand, and graduated from the University of Otago. As an educator he rose to the position of inspector of schools for the New Zealand Education Department and made a significant contribution to the introduction of the new mathematics curriculum. He wrote text books that were extensively used in New Zealand primary schools and which were also published in the United States. In 1958 he moved to the North America as a university lecturer and he received his doctorate from Columbia University. Wikipedia
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