P-G (Guimarães) Arquivo Municipal Alfredo Pimenta C 0149
The two folios are consecutive: they contain the Masses for Holy Wednesday and Maundy Thursday and the initial antiphons for the Mandatum rite; it belonged to a section of chants for Holy Week.
Very interesting are the three Antiphons on f. B verso, for Maundy Thursday. These Antiphons are not referred to in the Missal of Braga.
A marginal unreadable note on f. Ar right side. On B verso there is a library sticker with the numbers: 1722 and some more numerals deleted and now unreadable.
Harmonies of Heaven and Earth: The music in the manuscripts of Guimarães (12th – 17th centuries), Guimarães, Museu de Alberto Sampaio, 2012. ISBN 978-989-97732-1-9