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Softcover published 1963 by Ibadan University Press. The "crocodile skin" textured wraps are lightly worn on the edges, with some dog-earing. Internally, the top corners of the pages are also dog-eared to a degree, but though generally aged, the pages are otherwise clean and unmarked. Dedicated by the author on the title page. "Based on a lecture given before the Philosophical Society, University College, Ibadan, on 14 February 1962".
