P-BRad (Braga) Arquivo Distrital Pastas de fragmentos, 028 (olim Caixa 288, nº 3)
On fol Bv above the incipit of the Offertorium "Angelus Domini" an ancient hand provided the folio number where the full chant could be originally read.
"28" written in red ink by a modern hand between the two columns on fol. Ar. On the upper right corner of the same folio a modern hand wrote "Caixa 288 n. 3" in blue ink.
Further inscriptions written on fols. Ar and Bv (along the left border) provide information on the provenance of the fragment, which was used as book cover in the Tombo of Santa Marinha of Peruzello (in 1541). Prozelo is located ca 15 km north-east of Braga.
COSTA Avelino Jesus da, "Pergaminhos Medievais: Inventário Ideográfico e Bibliográfico", Braga, Seminário de Nossa Senhora da Conceição, 1944-1952, 9.vols, polycopied script. VEIGA Diogo Alte da, "O Alleluia na monodia litúrgica em Portugal até 1600: comparações melódicas", master’s dissertation (Nova University of Lisbon, November 2009).