For further details about the formation of the canon, as well as challenges to the notion of the settling of the canon in the fourth century, see the work of Lee Martin McDonald, including The Biblical Canon: Its Origin, Transmission, and Authority, 3rd ed. (Peabody, MA: Hendrickson, 2007) and The Formation of the Bible: The Story of the Church’s Canon (Peabody, MA: Hendrickson, 2012).