general instruction of the roman missal liturgy documentary series i

GENERAL INSTRUCTION OF THE ROMAN MISSAL
a. seats and texts for the
concelebrating priests;
b. on the credence table: a chalice of
sufficient size or else several
chalices.
208. If a deacon is not present, his proper
duties are to be carried out by some of
the concelebrants.
In the absence also of other ministers,
their proper parts may be entrusted to
other suitable members of the faithful;
otherwise, they are carried out by some
of the concelebrants.
209. In the vesting room or other suitable
place, the concelebrants put on the
sacred vestments they customarily wear
when celebrating Mass individually.
Should, however, a good reason arise,
(e.g., a large number of concelebrations
or a lack of vestments), concelebrants
other than the principal celebrant may
omit the chasuble and simply wear the
stole over the alb.
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