Ecce ego mitto vos sicut

Source: 
Wolfenbüttel, Herzog August Bibliothek - Cod. Guelf. 28 Helmst. (Heinemann-Nr. 31)
Folio: 
028r
Sequence: 
8
Feast: 
Comm. Apostolorum
Office/Mass: 
V
Genre: 
A
Cantus ID: 
002512
Mode: 
1
Differentia: 
D1
Differentia database: 
1--h-h-g-f-g-gfed--4 75d
Extra: 
001r
Indexing notes: 
If it's a duplex feast, then this is the antiphon for the psalms;