Liber misticus (type of book with chants, readings and prayers for the cathedral ordo) with material for Lent (Wednesdays, Fridays, Sundays and Holy Week) and for the beginning of Eastertide (Easter Sunday and Easter Monday - after this it ends with a lacuna). It starts halfway through the farewell to the alleluia office (in the middle of its matutinum service), which this manuscript numbers as the first Sunday of Lent (the Antiphonary of León, instead, call this office "Carnes Tollendas" Sunday).

Date: After studying its palaeographical features Mundó (1965) proposed mid-thirteenth century as the copy-date for this manuscript and most authors have adopted this date. Other dates: "IX?" (Brockett, 1968); ninth to tenth century (Millares Carlo, 1961; García Villada, 1923); tenth to eleventh century (Riaño, 1887; Férotin, 1912, specifying to the beginning of the eleventh century; Clark, 1920; Rojo and Prado, 1929); ninth to tenth century but also quoting Mundó's date (Randel, 1973; Gómez Muntané, 2001); eleventh to twelfth century but also quoting Mundó's dates (Millares Carlo, 1999).

Provenance: most authors associate it with the parish of Santas Justa y Rufina of Toledo because its repertoire coincides with that in manuscript E-Mn MS/10100. However, these manuscripts are palaeographically and codicologically different. It might have been copied for any Mozarabic parish of Toledo (see Rojo, 2017).

Tradition: B.

Randel responsorial tone tradition: Toledo B.