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by Enrique Anderson Imbert (Harvard University); Eugenio Florit (Barnard College, Columbia University)
by Ginger, Ray
by Fischer, David Hackett
by University of Chicago School Mathematic Project
by OPEN UNIVERSITY
by Wolfe, Charles K.
by Harvard University Press
by Richard Middleton (The Queen's University, Belfast)
by Lewis, C.S.
by Michell, George
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