P-Cug (Coimbra) Biblioteca Geral da Universidade MM 1063-74 + MM 230 + MM 231
A1r, voice-parts named in Portuguese: "alta", "tenor", "baixa"; A1v: "tenor"; C1v, folding of the outer face: "bassus". B1r: "SVPERIVS :-" C1r: "ALTVS" (referring to the contents of partbooks MM 230 and 231 respectively).
Three folios from the same choirbook. Folios B1-C1 and B2-C2 are still serving as covers to partbooks MM 230 and MM 231.
B1 (front cover of MM 230) and C1 (front cover of MM 231) are the top half and the bottom half of the same folio respectively; the outer face of B1 and C1 originally formed an opening with Av (MM 1063-74).
B2 (back cover of MM 230) is also part of the same folio as C2 (back cover of MM 231).
The inner faces of the back covers of MM 230 and MM 231 have fragments of a chant book inserted, reinforcing them.
The scribe of the polyphonic fragments is different from those working on the earliest surviving complete or nearly complete choirbooks copied in Santa Cruz, dated to the 1540s and 50s.
The set of partbooks that includes MM 230 and MM 231 is described in http://pemdatabase.eu/source/97592. The third book in the set, MM 161, also has covers of the same provenance but their original content is illegible to such an extent that it does not allow for any identification.