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to the study of the choir books of Santa Maria del Popolo, gleanings from the documentary sources and a look at two (unpublished) illuminated graduals by the Master of the Barbo Missal”, Bibliothecae.it, 12(2), pp. 257–305. doi: 10.6092/issn.2283-9364/18713.