• P.V. Spade (trans.), Five Texts on the Mediaeval Problem of Universals: Porphyry, Boethius, Abelard, Duns Scotus, Ockham (Indianapolis: 1994).

• I. Iwakuma, “Vocales, or Early Nominalists,” Traditio 47 (1992): 37-111.

• A. de Libera, La querelle des universeaux: De Platon à la fin du Moyen Age (Paris: 1996).

• J. Marenbon, Aristotelian Logic, Platonism and the Context of Early Medieval Philosophy in the West (Aldershot: 2000).

• M. Tweedale, “Abelard and the Culmination of Old Logic,” in N. Kretzmann, A. Kenny and J. Pinborg (eds), The Cambridge History of Later Medieval Philosophy (Cambridge: 1982), 142-57.

• Vivarium 30 (1992): special journal issue on logic in the 12th century with several papers on Roscelin and Abelard.

Stanford Encyclopedia: The Medieval Problem of Universals

Stanford Encyclopedia: William of Champeaux