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Anon. (1901). Emininent Living Geologists: Professor T. G. Bonney, from the Geological Magazine, pp 385-400 + portrait plate. Geological Magazine.
O’Donoghue, Y. (1972). William Roy 1726-1790; Pioneer of the Ordnance Survey. London: British Museum, first edition, 56pp. Paperback,. Ordnance Survey.
Portlock, JE (1869). Memoir of the Life of Major-General Colby, together with a Sketch of the Origin and Progress of the Ordnance Survey of Great Britain and Ireland: . Skeely Jackson.