 Within the melisma the melodic interval of the fourth is prominent and is repeated several times, and several modes, including Phrygian, Dorian and Mixolydian, are implied, giving it an extraordinary melodic diversity.While originally the "Caput" mass was thought to have been by Guillaume Du Fay – since it is attributed to him in its most complete source, the Trent Codices – recent research has established that it originated in England.The cyclic mass has been shown to be a development of English origin, enthusiastically taken up by composers of the Burgundian School, and eventually becoming the primary vehicle for long-span musical expression in the High Renaissance.