How the Copies were provided
Such were the emperor's commands, which were followed by the immediate execution of the work itself, which we sent him in magnificent and elaborately bound volumes of a threefold and fourfold form. This fact is attested by another letter, which the emperor wrote in acknowledgment, in which, having heard that the city Constantia in our country, the inhabitants of which had been more than commonly devoted to superstition, had been impelled by a sense of religion to abandon their past idolatry, he testified his joy, and approval of their conduct.
Source: Life of Constantine (New Advent)