Bede's Ecclesiastical History of England, ed. by A.M. Sellar, , at sacred-texts.com
Moreover, the same Pope Gregory, hearing from Bishop Augustine, that the harvest which he had was great and the labourers but few, sent to him, together with his aforesaid envoys, certain fellow labourers and ministers of the Word, of whom the chief and foremost were Mellitus, Justus, Paulinus, and Rufinianus, and by them all things in general that were necessary for the worship and service of the Church, to wit, sacred vessels and altar-cloths, also church-furniture, and vestments for the bishops and clerks, as likewise relics of the holy Apostles and martyrs; besides many manuscripts. He also sent a letter, wherein he signified that he had despatched the pall to him, and at the same time directed how he should constitute bishops in Britain. The letter was in these words:
"To his most reverend and holy brother and fellow bishop, Augustine, Gregory, the servant of the servants of God. Though it be certain, that the unspeakable rewards of the eternal kingdom are reserved for those who labour for Almighty God, yet it is requisite that we bestow on them the benefit of honours, to the end that they may by this recompense be encouraged the more vigorously to apply themselves to the care of their spiritual work. And, seeing that the new Church of the English is, through the bounty of the Lord, and your labours, brought to the grace of God, we grant you the use of the pall in the same, only for the celebration of the solemn service of the Mass; that so you may ordain twelve bishops in different places, who shall be subject to your jurisdiction. But the bishop of London shall, for the future, be always consecrated by his own synod, and receive the pall, which is the token of his office, from this holy and Apostolic see, which I, by the grace of God, now serve. But we would have you send to the city of York such a bishop as you shall think fit to ordain; yet so, that if that city, with the places adjoining, shall receive the Word of God, that bishop shall also ordain twelve bishops, and enjoy the honour of a metropolitan; for we design, if we live, by the help of God, to bestow on him also the pall; and yet we would have him to be subject to your authority, my brother; but after your decease, he shall so preside over the bishops he shall have ordained, as to be in no way subject to the jurisdiction of the bishop of London. But for the future let there be this distinction as regards honour between the bishops of the cities of London and York, that he who has been first ordained have the precedence. But let them take counsel and act in concert and with one mind dispose whatsoever is to be done for zeal of Christ; let them judge rightly, and carry out their judgement without dissension.
"But to you, my brother, shall, by the authority of our God and Lord Jesus Christ, be subject not only those bishops whom you shall ordain, and those that shall be ordained by the bishop of York, but also all the prelates in Britain; to the end that from the words and manner of life of your Holiness they may learn the rule of a right belief and a good life, and fulfilling their office in faith and righteousness, they may, when it shall please the Lord, attain to the kingdom of Heaven. God preserve you in safety, most reverend brother.
"Given the 22nd of June, in the nineteenth year of the reign of our most religious lord, Mauritius Tiberius Augustus, the eighteenth year after the consulship of our said lord, and the fourth indiction."