What is a "Daud of Sons" as stated in Definition of Faith of the Council of Chalcedon?

In my copy of _Readings in World Christian History Volume 1: Earliest Christianity to 1453_, edited by John W. Coakley & Andrea Sterk, the 35th text, starting on page 175, entitled "Definition of Faith of the Council of Chalcedon", is a text regarding the Council of Chalcedon, and in it, the author says that "for it [Truth, as best I can tell] opposes those who would render the mystery of the dispensation [i.e. the Incarnation] in a **Daud of Sons**;" (emphasis mine) My question is, what is a "Daud of Sons," and how would false teachers make the Incarnation into such a thing? Here's a link to an online copy I found that seems to be the same translation Definition of Faith of the Council of Chalcedon