Tu es Petrus et super*

Source: 
Chicago, Newberry Library, 24
Folio: 
197r
Sequence: 
11
Feast: 
Vincula Petri
Office/Mass: 
L
Genre: 
A
Position: 
5
Cantus ID: 
005208
Mode: 
7
Differentia: 
C1
Differentia database: 
1--l-l-m-l-k-jk--4 144a
Extra: 
a