Perotin - Organum quadruplum: Viderunt (Excerpt) (ca. 1200) from CD “PEROTIN” ECM New Series 1385 422 837 751-2 (recorded September 1988) THE HILLIARD ENSEMBLE

As preserved in Florence, Biblioteca Medicea-Laurenziana, Pluteus 29.1, fol. 1-4: