Signorello, L. 2023. «Questa sie la resone de li libri che se fano del choro di Sancta Maria del Popolo»: Prolegomena to the study of the choir books of Santa Maria del Popolo, gleanings from the documentary sources and a look at two (unpublished) illuminated graduals by the Master of the Barbo Missal. Bibliothecae.it. 12, 2 (Jan. 2023), 257–305. DOI:https://doi.org/10.6092/issn.2283-9364/18713.