On the Power of the Patriarchs over Surrounding Sees

Balsamon, RP2, 171,
Take notice from the present canon that formerly all the metropolitans of the provinces were themselves heads of their own provinces, and were ordained by their own synods. But all this was changed by Canon 28 of the Synod of Chalcedon, which directs that the Metropolitans of Pontos, Asia, and Thrace, and certain others which are mentioned in this Canon should be ordained by the Patriarch of Constantinople and should be subject to him.
The translation here is from Percival, 177.