B-Br II 266 (cat.nr. 714)
One of the folders with liturgical fragments of the Albertina. This folders contains fragments from the 11th century and younger.
The first fragment is from an 11th century missal with Low Countries notation, and shows some resemblance with Berne, LM 1, though it is less elegant.
Fragment 10 of the folder contains polyphony in mensural notation.