* Malcolm Barber, "The New Knighthood" (Great Britain; Cambridge University Press, 1994), p. 74-75* Smail, R. C. "Crusading Warfare 1097-1193.
*Malcolm Barber, "The New Knighthood" (Great Britain; Cambridge University Press, 1994), p. 74-75* Smail, R. C. "Crusading Warfare 1097-1193.