1. KerNR William Hunter as a Collector of Medieval Manuscripts. Glasgow: University of Glasgow Press, 1983: 20.
2. ThorpN In: MillerH, ed. The Glory of the Page: Medieval Manuscripts from Glasgow University Library. Glasgow University Library and the Art Gallery of Ontario, 1987: 97.
3. EldredgeLM The Wonderful Art of the Eye: A Critical Edition of the Middle English Translation of de Probatissima Arte Oculorum. Michigan State University Press, 1996: 49.
4. LindbergDC A Catalogue of Medieval and Renaissance Optical Manuscripts. Toronto: Pontifical Institute for Medieval Studies, 1975: 102–5.