The mystics leaned to rigid unity, and in the sixth century Saint Gregory published his 'Antifonario,' a collection of all Liturgic melodies, purifying them according to his ideas.
"The Shadow of the Cathedral"
Vicente Blasco Ibañez
Perhaps no loss caused by the general wreck of ancient literature has been more disastrous than that of the Liturgic books of paganism.
"The Oriental Religions in Roman Paganism"
Franz Cumont
By studying the arrangement of the temples and the religious furniture that adorned them, one can at the same time determine part of the Liturgic ceremonies which took place there.
"The Oriental Religions in Roman Paganism"
Franz Cumont