Opera S. Anselmi. Pastedowns, now lifted, which bear a motet with a Flemish text on the front leaf. There is also the discantus of a Gloria for 3 voices with concordances in 5 other MSS. Boards front & back have mirror image offsets of the lifted pages which are in some respects easier to read. The pastedowns are now part of MS B 1328.
See also Lerch's reconstruction of these and other fragments as 'F-CA(n)'.