|Canterbury Cathedra; Miracle Window|
Mad Matilda of Cologne
Edwin Abbott Abbott (1898). St. Thomas of Canterbury: his death and miracles. Volume 1. A. and C. Black. pp. 314–5.
J.C. Robertson and J.B. Sheppard (eds.), Materials for the History of Thomas Becket, vol. II (London, 1876), pp. 208-209. -
§  The madness of Matilda of Cologne