Snyder. The Britons. p. 123.; Jones.The End of Roman Britain. pp. 44–45.; Morris. Dark Age Dates. p. 154.; Michael Wood. The Domesday Quest. p. 64.; Bede.EH. Book 1. Ch. 15–16.; Annales Cambriae.
Gildas. The Ruin of Britain 23. Gildas says that it is Saxons who come over to fight the Picts and settle, whereas Bede, HE.Book 1 Ch 15 suggests that it is Angles or Saxons.