Genre: 
Full text: 
Gloria patri | Increato nec genito | Et filio | Increato sed genito | Et spiritui sancto | Septiformis largitori gratiae | Cujus igne purgamur a crimine
Feast: 
Fulltext source: 
"Bijdrage tot de Geschiedenis van het liturgisch Drama in de Nederlanden" (online, Internet Archive)
Notes: 
This appears to be a troped Gloria patri (but in Utrecht 406 with the melody of the responsory prosa that precedes it, instead of a recitation tone).