The fragment most likely once formed part of a choirbook copied in Paris or Avignon in the mid‑fourteenth century, which eventually found its way to the collegiate church in Brussels. It contains four motets: two anonymous works and two by the French composer Philippe de Vitry. The source was digitized as part of REIMAGE (Reimaging and Re‑enacting Polyphony), a research project in partnership with the University of Geneva that aims to reconstruct damaged and incomplete musical fragments from the Low Countries dating from 1300–1430 using multispectral imaging.

The mobile lab then moved on to the Royal Library of Belgium. There the ADL team digitized a ‘picture motet’ from Rome dated around 1617. The engraving depicts Pope Gregory I and a choir of angels presenting a score with a four‑voice setting of the Marian antiphon Regina coeli by the Italian composer Francesco Soriano. Several incunabula from Paris and Cologne were digitized as well.

The sources are now being further studied by the Alamire Foundation, after which the images, accompanied by detailed metadata, will be published on the website of the Integrated Database for Early Music.