1) D HC 2/11/5  Not dated [circa 1312-1316] Contents: Gift by Gilbert, son of the late Gilbert de Sleagill, to William, son of Adam de Derwentwater: all his lands and tenements which William son of William de Wirkyngton [Workington] formerly held under him in Sleagill, and all the estate that the said William, son of William de Wirkygton quitclaimed to him, Witnesses include Sir Thomas de Derwentwater. National Archive Howard Family of Corby. Accessed 30-01-2013.