I'd never seen this before today when I was trying to answer a question on the natures of God, but St. Cyril's 12 Anathemas against Nestorius is pretty interesting, and as a piece of literature, I think it's pretty unique.
This is from the first of the Anathemas:
If anyone will not confess that the Emmanuel is very God, and that therefore the Holy Virgin is the Mother of God (Θεοτόκος), inasmuch as in the flesh she bore the Word of God made flesh [as it is written, "The Word was made flesh"] let him be anathema.
Nestorius: If anyone says that the Emmanuel is true God, and not rather God with us, that is, that he has united himself to a like nature with ours, which he assumed from the Virgin Mary, and dwelt in it; and if anyone calls Mary the mother of God the Word, and not rather mother of him who is Emmanuel; and if he maintains that God the Word has changed himself into the flesh, which he only assumed in order to make his Godhead visible, and to be found in form as a man, let him be anathema.
Is the first part St. Cyril and the second part Nestorius himself? Or is the whole thing St. Cyril and the part that starts with Nestorius:
just St. Cyril writing what he believe are the problems with Nestorius's theology?