References for John 1st Earl de Lacy * of Lincoln
F.M.Powicke, E.B.Fryde: Handbook of British Chronology. London, 1961
D.Schwennicke: Europäische Stammtafeln, Vol. III/4, Tafel 709. Marburg, 1989
W.E.Wightman: The Lacy Family in England and Normandy 1066-1194. Clarendon Press, 1966