325. Sources and Bibliography. -- EHRLE's essays, see 240. Peckham's letters have also been published by WILKINS, Concilia Magnae Britanniae et Hiberniae, ii., 107; Registrum epistolarum J. Peckham, MARTIN'S edit., iii., 840; some also in the Chartul., i. DENIFLE, Quellen z. Gelehrtengesch. d. Predigerord., see 237. We have edited the De Unitate Formae of Giles of Lessines, according to two MSS., Paris and Brussels, with a critical introduction. See 240. STAPPER, Die Summulae Logicales des P. Hispanus (Freiburg, 1897) and Papst Johannes XXI. (Kirchenhistor. Studien, iv., Münster, 1898). WALSH, John XXI., Philosopher, Physician, Pope (American Eccles. Review, 1908). A. LECLÈRE, Le mysticisme catholique et l'âme de Dante (Paris, 1906). CARBONI, La Sintesi Filosofica del Pensiero Dantesco (Pitigliano, 1899). P. BERTHIER, La Divina Comedia con Commenti secondo la Scolastica (Turin, 1893 sqq.). A. NIGLIS, Siger von Courtrai, Beiträge zu seiner Würdigung (Freiburg, 1903): life and analysis of works. DE WULF and PELZER, Les Quatre Premiers Quodlibets de G. de Fontaines (t. ii. of Les Philosophes Belges, Louvain, 1904): critical edition of a "textus reportatus" based on four MSS. Quodl. v.-xiv., after Godfrey's own text, will shortly appear (tt. iii. and iv. of the collection), together with an exhaustive study of the philosopher himself (t. v.) by a number of different writers. DE WOLF, Études sur la vie, les oeuvres et l'influence de G. de Fontaines (Louvain, 1904; memoir crowned by the Belgian Academy). The principal works of Giles of Rome are to be found in numerous Italian editions of the fifteenth and sixteenth centuries, enumerated by WERNER (see below), pp. 16 and 17, note. Cf. The philosophy of Giles of Rome deserves to be better known. LAJARD, Gilles de Rome (Hist. Litt. France, t. 30, pp. 421-566): deals only with his life and works. WERNER, Der Augustinismus d. späteren Mittelalters (Vienna, 1883), (t. iii. of the collection: Die Scholastik d. späteren Mittelalters): studies especially the doctrines of Giles of Rome and Gregory of Rimini; but Werner's historical views are unreliable. A number of writers (KAUFMANN, etc.) have published (Herder, 1904): AEgidius Romanus de Colonna, Joh. Gersons, Dionys. d. Karthausers n. J. Sadolets pädagogische Schriften, German trans. The Quodlibeta of Henry of Ghent were edited at Paris (1518) and Venice (1608, 1623); the Summa Theologica, at Paris (1580) and Ferrara (1646): all very rare editions. We hope to publish a critical edition of both works in the collection Les Philosophes Belges. DE WULF, Études sur Henri de Gand (1895): biographical researches and critical exposition of doctrines. This work is an extract from a larger volume: Histoire de la Philos. scolast. ds. les Pays-Bas et la Principauté de Liége jusqu'à la Revoint. Française (Louvain, 1895; memoir crowned by the Belgian Academy).