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 II

Canon II.

Of Preaching the Trinity.

The whole Council said:  By the favour of God, by a unanimous confession the Church’s faith which through us is handed down should be confessed in this glorious assembly before anything else; then the ecclesiastical order of each is to be built up and strengthened by the consent of all.  That the minds of our brethren and fellow bishops lately elevated may be strengthened, those things should be propounded which we have certainly received from our fathers, as the unity of the Trinity, which we retain consecrated in our senses, of the Father, and of the Son, and of the Holy Ghost, which has no difference, as we say, 422 so we shall instruct the people of God.  Moreover by all the bishops lately promoted it was said:  So we openly confess, so we hold, so we teach, following the Evangelic faith and your teaching.

Notes.

Ancient Epitome of Canon II.

No difference is recognised or taught by the decrees of the Council of Nice between the Persons of the Holy Trinity.

This canon, or rather introduction, is taken from Canon j., of the Council of Carthage held under Genethlius, a.d. 387 or 390. 423

Footnotes

Or “have learned.”

In assigning these canons to the several synods that adopted them, I have simply followed Hefele.