^ abPalazzo, Eric (1998). A History of Liturgical Books from the Beginning to the Thirteenth Century. Liturgical Press. p. 169. ISBN9780814661673. It is the Franciscan breviary deriving from the second rule of the order approved by Innocent III in 1223 that for the first time expressly bears the name breviarium: Clerici facient divinum offocoum secundum ordinem sanctae Romanae Ecclesia excepto Psalterio, ex quo habere poterunt breviaria ["The clerics will celebrate the Office according to the ordo of the holy Roman Church, except for the psalter which they may use in shortened forms"].
^Smith, William; Cheetham, Samuel (1 January 2005). Encyclopædic Dictionary Of Christian Antiquities. Concept Publishing Company. p. 247. ISBN9788172681111. The contents of the breviary, in their essential parts, are derived from the early ages of Christianity. They consist of psalms, lessons taken from the Scriptures, and from the writings of the Fathers, versicles and pious sentences thrown into the shape of the antiphons, responses, or other analogous forms, hymns and prayers.
^Lewis, George (1853). The Bible, the missal, and the breviary; or, Ritualism self-illustrated in the liturgical books of Rome. T. & T. Clark. p. 71. The Goths of Spain had their Breviary; the French Church had its Breviary; England--"the Breviary of Salisbury"--and Scotland, "the Breviary of Aberdeen"--all which, along with many more evidences of the independence of national churches, Rome has laboured to obliterate by commanding the exclusive use of the Roman Breviary, and thus extinguishing every appearance of a divided worship, and of independent national and self-regulated churches.|access-date= requires |url= (help)
^Hart, Addison H. ""Prayer Rhythms" Redivivus". Touchstone. The Fellowship of St. James. Retrieved 3 May 2015. The Reverend Frank Gavin had himself suggested such a work as early as 1916.