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by OPEN UNIVERSITY
by Veysey, Laurence R.
by Richard Middleton (The Queen's University, Belfast)
by University of Chicago School Mathematic Project
by Thomas H. Wonnacott (University of Western Ontario); Ronald J. Wonnacott (University of Western Ontario)
by Cambridge University Press
by Ralph Fasold (Georgetown University)
by Hargrove, Erwin C.
by Michael T. Clanchy (University of London)
by Delores M. Etter (University of Colorado, Boulder)
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