Thomas of Selkirk appears in 1291 and in 1318 (G. W. S. Barrow ‘The Aftermath of War: Scotland and England in the Late Thirteenth and Early Fourteenth Centuries: The Prothero Lecture’, <em>Transactions of the Royal Historical Society</em>, Fifth Series, Vol. 28 (1978), pp. 103-125 (p. 106-7)).