1. Robert A. MacDonald, ‘Law and Politics: Alfonso’s Program of Political Reform’, in The Worlds of Alfonso the Learned and James the Conqueror: Intellect and Force in the Middle Ages, ed. Robert I. Burns S.J. (Princeton, 1985), p. 181. For Alfonso’s main law code see Las Siete Partidas, trans. Samuel Parsons Scott, ed. Robert I. Burns, S.J., 5 vols (Philadelphia, 2001). A preliminary variant of the present reflections can be found in 7: xxvi–xxxv.
2. Joseph F. O’Callaghan, The Learned King: the Reign of Alfonso X of Castile (Philadelphia: 1993), and his Alfonso X and the Cantigas de Santa Maria: a Poetic Biography (Leiden, 1998 )
3. Manuel González Jiménez, Alfonso X, 1252–1284, in the Corona de España, Reyes de Castilla y León series (Palencia: 1993). For most purposes, these biographies replace the huge and unwieldy Alfonso X el Sabio by Antonio Ballesteros Beretta (Madrid: 1964, and with indexes Barcelona: 1984)
4. An introduction and summary for the Siete Partidas is John E. Keller, Alfonso X, el Sabio in the Twayne World Authors series (New York, 1967), pp. 116–33
5. For Alfonso’s cultural-legal-scientific achievements, see Robert I. Burns S. J. (ed.) Emperor of Culture: Alfonso X the Learned of Castile and his Thirteenth-Century Renaissance, (Philadelphia, 1990 ).