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 CV

Of those who do not communicate in Africa and would go across seas. Whoever does not communicate in Africa, and goes to communicate across seas, let him be cast out of the clergy. Whoever is cut off from communion in Africa, and goes to parts across seas that he may there communicate, is to be cast out of the clergy. This canon is Canon j. of Carthage, a.d. 407.