"1400 - 1499" . . . . . . . "Analyzing four-voice vertical sonorities in fifteenth-century sacred polyphony a comparison of selected Ockeghem Kyries according to contrapuntal theory of Pietro Aaron"@en . "Analyzing four-voice vertical sonorities in fifteenth-century sacred polyphony : a comparison of selected Ockeghem kyries according to contrapuntal theory of Pietro Aaron"@en . "History"@en . . . . . . . . . "Criticism, interpretation, etc"@en . "Analyzing four-voice vertical sonorities in fifteenth-century sacred polyphony : a comparison of selected Ockeghem Kyries according to contrapuntal theory of Pietro Aaron"@en . . . . . . . "Analyzing four-voice vertical sonorities in fifteenth-century sacred polyphony : a comparison of selected Ockeghem kyries according to contrapunctal theory of Pietro Aaron" . . . . . .