Source: PL-Wn 12496 IV Graduale cistercienseFolio: 068rSequence: 25Feast: Petri, Mart.Office: MASSGenre: AllCantus ID: g02236Mode: *Full text: Alleluia Laetabitur*Notes: the formulary added later (the second one)Marginalia: BExternal image link: Image link