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3. Browne J. (1825) A Critical Examination of Dr. MacCuilloch's work on the Highlands and Western Islands of Scotland (D. Lizars, Edinburgh).
4. Clarke J. W. Hughes T. M. (1890) The Life and Letters of the Reverend Adam Sedgwick (Cambridge University Press, Cambridge), 2 vols.
5. Close C. (1926) in The Early Years of the Ordnance Survey, ed Harley J. B. (David & Charles, Newton Abbott and Augustus M. Kelley, New York) Institution of the Royal Engineers, London; reprinted 1969.