Purkis, William J. Crusading Spirituality in the Holy Land and Iberia, c.1095-c.1187 (2014.), str. 140.
Van Herwaarden, J. Between Saint James and Erasmus: Studies in Late-Medieval Religious Life: Devotions and Pilgrimages in the Netherlands (2003.), str. 359.
Thomas Deswarte in: Culture and Society in Medieval Galicia: A Cultural Crossroads at the Edge of Europe (2015.), str. 498.