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 XI

Canon XI.

If any presbyter, inflated against his bishop, makes a schism, let him be anathema.

All the bishops said:  If any presbyter shall have been corrected by his superior, he should ask the neighbouring bishops that his cause be heard by them and that through them he may be reconciled to his bishop:  but if he shall not have done this, but, puffed up with pride, (which may God forbid!) he shall have thought it proper to separate himself from the communion of his bishop, and separately shall have offered the sacrifice to p. 448 God, and made a schism with certain accomplices, let him be anathema, and let him lose his place; and if the complaint which he brought against his bishop shall [not] have been found to be well founded, an enquiry should be instituted.

Notes.

Ancient Epitome of Canon XI.

A Presbyter condemned by his bishop, is allowed to appeal to the neighbouring bishops:  but if he shall not make any appeal, but shall make a schism, and be elated with conceit and shall offer the Holy Gifts to God, let him be anathema.

See note to last canon.  The last clause is certainly corrupt; in the council of Carthage at which it was first adopted there is no “non,” making the meaning clear.