C. Arnold McNaughton, The Book of Kings: A Royal Genealogy, in 3 volumes (London, U.K.: Garnstone Press, 1973), volume 1, p. 155
G.E. Cokayne; with Vicary Gibbs, H.A. Doubleday, Geoffrey H. White, Duncan Warrand and Lord Howard de Walden, editors, The Complete Peerage of England, Scotland, Ireland, Great Britain and the United Kingdom, Extant, Extinct or Dormant, new ed., 13 volumes in 14 (1910-1959; reprint in 6 volumes, Gloucester, UK: Alan Sutton Publishing, 2000), volume XIII, p. 262
L. G. Pine, The New Extinct Peerage 1884-1971: Containing Extinct, Abeyant, Dormant and Suspended Peerages With Genealogies and Arms (London, U.K.: Heraldry Today, 1972), p. 52