Nicene and Post-Nicene Fathers, Ser. II, Vol. XIV:
The Canons of the Synods of Sardica, Carthage, Constantinople, and Carthage Under St. Cyprian, Which Canons Were Received by the Council in Trullo and Ratified by II. Nice.: Canon XCI

Canon XCI.  (Greek xciv.)

Of holding meetings with the Donatists.

Aurelius, the bishop, said:  What has come out in the handling of your charity, I think this should be confirmed by ecclesiastical acts.  For the profession of all of you shews that each one of us should call together in his city the chiefs of the Donatists either alone and with one of his neighbour bishops, so that in like manner in the different cities and places there should be meetings of them assembled by the magistrates or seniors of the places.  And let this be made an edict if it seems good to all.  And all the bishops said:  It seems good to all, and we all have confirmed this with our subscription.  Also we desire that your holiness sign the letters to be sent from the council to the judges.  Aurelius, the bishop, said:  If it seems good to your charity, let the form of summoning them be read, in order that we all may hold the same tenour of proceeding.  All the bishops said:  Let it be read.  Lætus the Notary read.

Notes.

Ancient Epitome of Canon XCI.

Let each of the bishops meet with the leaders of the Donatists in his own city; or let him associate with himself a neighbouring bishop, that they together may meet them.

This introduction together with the propositions of the different bishops belongs to the Synod of Carthage of August, 403.

This canon (xcj.) is Canon j. of that synod.