Paetow Paetow (L. J.), _The arts course at medieval universities with special reference to grammar and rhetoric_, University of Illinois Studies, vol. 3, No. 7, Jan., 1910. See also the bibliography in his _Guide to the study of medieval history_, University of California Press, 1917. PL _Patrologia latina_ (Migne) cited by volume and column. Polheim Polheim (K.), _Die lateinische Reimprosa_, Berlin, 1925. Poole Poole (R. L.), _Lectures on the history of the Papal chancery ..._, Cambridge (University Press), 1915. Rockinger Rockinger (L.), _Briefsteller und Formelbücher ..._, 2 vols., Munich, 1863-1804, Quellen zur bayerisch. u. deutsch. gesch. Thurot Thurot (C.), _Notices et extraits ... pour servir à l’histoire des doctrines grammaticales au moyen âge_, Paris, 1868, in NE 22, part 2 (entire). Toynbee Toynbee (P.), _Dantis Alagherii epistolæ ..._ with introduction, translation, notes, and indices, and appendix on the _cursus_, Oxford, 1920. Vacandard Vacandard (E.), _Le cursus, son origine, son histoire, son emploi dans la liturgie_, Revue des questions historiques, n. s., 34 (1905): 59-102. Valois Valois (N.), _De arte scribendi epistolas apud gallicos medii ævi scriptores rhetoresve_, Paris, 1880, in Bibl. de l’École des Chartes, 22: 161, 257. The art of letter-writing, especially the composition of official and other ceremonious letters, was of cardinal importance in the middle age. Even to-day, when letters of affairs are facilitated and multiplied by devices for dictation and despatch, it has a field smaller than the medieval in proportion to the other means of communication. Since these conditions lasted into modern times, letter-writing kept its importance throughout the Renaissance; but its art, developed in Latin antiquity and keeping for all affairs of moment the Latin language, became in the middle age a necessary ally alike to law and to diplomacy. _Dictamen_ was a recognized profession and an habitual means of education. The model for the official correspondence of the western world was the Papal Chancery. The chief center of teaching was Bologna.[1] Though there was rivalry at Orléans, there was a recognized primacy of _stilus Romanus_.