Of the Mass, or an abbreviation for the Office in which the chant is sung
If of the Office, then CANTUS codes are used
1: group
Type= Choice: (1) Mass (2) V (3) C (4) M (5) L (6) D (7) P (8) T (9) S (10) N (11) V2 (12) E (13) H (14) R (15) X // Required= Yes
Contained In:
<accession_x> ... </accession_x>
Required: No
Repeating: No
Contains Character Data: No
Example of Use:

<service group="Mass"/>

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