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De la Rue Agnus L'homme arm. Pierre de la Rue's Missa L'homme arm notated as canon in four mensurations Heinrich Glareanus Dodecachordon Book III Basel cf online chmtl indiana edu chmtl indiana edu html Facsimile after Willy Apel Die Notation der polyphonen Musik Leipzig Brenreiter Pierre de la Rue Custom marker PDold