11 Masses (1 includes Proper sections)
(Berchem)-1, (Berchem/Jaquet of Mantua)-1, (Hesdin)-1, (Jaquet of Mantua)-2, (Willaert)-4, anon-2
3 paper partbooks of an original 4 (D-ii + 84 + i folios, A-ii + 91, T-i + 81 + i), 160 x 220. D book has original ink foliation, 1-75 (number "6" omitted) + new pencil foliation, 1-7 + original ink foliation, 13-76 (last folio unnumbered); T has original ink foliation, 80-81 + 1-79. Original numbering of pieces, "Missa Prima," . . . "Missa Undécima" (several Masses now out of proper sequence due to misbinding or careless arrangement by scribes).
Original parchment covers cut from 16th-century chant manuscript. No index. Copied by two main scribes, who also wrote parts of PiacD (2), (3), (4), and (5); one Mass in A book copied by a third scribe. Some small inked calligraphic initials.
Mid 16th century. Probably copied in Piacenza.
Census-Catalogue of Manuscript Sources of Polyphonic Music 1400-1550