1. Jesse Byock, Viking Age Iceland (London, 2001), pp. 369–372.
2. John D. Cotts, The Clerical Dilemma: Peter of Blois and Literate Culture in the Twelfth Century (Washington, DC, 2009), pp. 113–115;
3. R. N. Swanson, The Twelfth-Century Renaissance (Manchester, 1999), pp. 43–50.
4. R. W. Southern, Saint Anselm: A Portrait in a Landscape (Cambridge, 1990), p. 128.
5. William Tronzo, ‘The Medieval Object-Enigma, and the Problem of the Capella Palatina in Palermo’, in Eva R. Hoffman (ed.), Late Antique and Medieval Art of the Mediterranean World (Oxford, 2007), pp. 317–349.