Ante-Nicene Fathers, Vol VII:
Lactantius: Chap. V.—That the prophetic women—that is, the Sibyls—declare that there is but one God

Chap. V.—That the Prophetic Women—That Is, the Sibyls—Declare that There is But One God.

It remains to speak of the prophetic women. Varro relates that there were ten Sibyls,—the first of the Persians, the second the Libyan, the third the Delphian, the fourth the Cimmerian, the fifth the Erythræan, the sixth the Samian, the seventh the Cumæan, the eighth the Hellespontian, the ninth the Phrygian, the tenth the Tiburtine, who has the name of Albunea. Of all these, he says that there are three books of the Cumæan alone which contain the fates of the Romans, and are accounted sacred, but that there exist, and are commonly regarded as separate, books of almost all the others, but that they are entitled, as though by one name, Sibylline books, p. 226 excepting that the Erythræan, who is said to have lived in the times of the Trojan war, placed her name in her book: the writings of the others are mixed together. 1457  

All these Sibyls of whom I have spoken, except the Cumæan, whom none but the Quindecemviri 1458 are allowed to read, bear witness that there is but one God, the ruler, the maker, the parent, not begotten of any, but sprung from Himself, who was from all ages, and will be to all ages; and therefore is alone worthy of being worshipped, alone of being feared, alone of being reverenced, by all living beings;—whose testimonies I have omitted because I was unable to abridge them; but if you wish to see them, you must have recourse to the books themselves. Now let us follow up the remaining subjects.  

Footnotes

[See Cyprian on Balaam, vol. v. p. 502, note 7. A hint as to the qualified inspiration of these women.]  

The appointed guardians of the Sibylline books. At first there were two; the number was afterwards increased to ten, and subsequently to fifteen, termed Quindecemviri.