Charlemagne's Archetype of Gregorian Chant
Kenneth Levy
Argues that the "Gregorian" repertory of Mass propers was fully neumed under Charlemagne, a century sooner than is generally supposed. The chief witness an "apocryphal" Offertory, Factus est repente for Pentecost. Affected are widely-held views concerning: (1) origin neumes; (2) impact oral-improvisational techniques on Gregorian chant; and (3) relationship Old Roman chant styles.
Journal of the American Musicological Society