[13.] S. Singer, Die Dichterschule von St. Gallen (Leipzig, 1922) Introd. (by Peter Wagner) 11.
[14.] Turner, supra, 570; J. M. Clark, The Abbey of St. Gall as a Center of Literature and Art (Cambridge, 1926) 31.
[15.] Annales Laurissenses, anno 757 (MGH, SS, I, 140).
[16.] Jaffé, Regesta, 2346 (1799); Notker Balbulus, Epistolae (MPL, 131, 1172); Gesta Caroli, II, 7.
[17.] F. H. Dudden, Gregory the Great ([ch. 2, note 9]) I, ch. VI Gregory at Constantinople.
[18.] P. Wagner, “Morgen- und Abendland in der Musikgeschichte,” Stimmen der Zeit, Bd. 114 (1927) 138.
[19.] Clark, The Abbey of St. Gall etc., 112; C. Diehl, Manuel d’Art Byzantin (Paris, 1910) 359-360, 362-3; M. Hauttmann, Die Kunst des frühen Mittelalters (Berlin, 1929) 51-62; J. Strzygowski, Origin of Christian Church Art (Oxford, 1923) 84.
[20.] Anal. Hymn., 51, Introduction, xvii-xix; extended lists of the later Latin hymns appear in J. Julian, Dictionary of Hymnology (London, 1925) 546, 547.
[21.] J. Mearns, Early Latin Hymnaries (Cambridge, 1913).
[22.] Walpole, Early Latin Hymns, ([ch. 1, note 3]) xi.