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2. Bailey, N., “Universal Etymological English Dictionary”, 2nd ed. (1731).
3. “A New English Dictionary on Historical Principles”, 2, 394 (Edited by Murray, J. S. H., 1893).
4. “New ‘Standard’ Dictionary of the English Language” (Funk and Wagnall, New York and London, 1949).
5. Sorby, H. C., Proc. Roy. Soc., 21, 442 (1873).