Spurious Writings in the Ante Nicene Fathers set

In a facebook group, "Early Church HIstory Study Group," my friend Errol Vincent Amey shared the following information concerning spurious writings in the Schaff Ante Nicene Fathers (10 vols.) set which I reproduce below: 

There are many good things to say about the Ante-Nicene Fathers series, including its unparalleled accessibility. But this series was translated during the mid to late 19th century, and there have been some notable advancements in patristic scholarship since then including identifying writings once thought to be genuine as actually being spurious forgeries. More often than not the people who appeal to these works simply don’t realize them to be dubious sources, but in recent exchanges in this group we have found instance of these works being appealed to as genuine even after their spurious nature was pointed out. So be aware of this should you see anyone appealing to the following forgeries.

• The Oration on Simeon and Anna, falsely attributed to Methodius:

“Certainly Spurious works: (a) De Simeone et Anna (P[atrologia]G[raeca] 18.347-82), a sermon which may be as late as the ninth century”
(Herbert Musurillo, Ancient Christian Writers 27:10)

• The First Homily on the Annunciation of the Holy Virgin Mary, falsely attributed to Gregory Thaumaturgus:

“Other than these writings, various others have come to us under the name of Gregory Thaumaturgus . . . . there are others that are certainly false: the treatise On the Soul to Tatian, which was written by Apollinaris, some homilies and another writing, regarding which see [Maurice Geerard] C[lavis]P[atrum]G[raecorum] 1,1772ff.”
(Manlio Simonetti, Encyclopedia of Ancient Christianity 2:188, bold added)

• The Declaration of Faith, falsely attributed to Gregory Thaumaturgus:

“I have taken what may be termed a ‘maximalist’ position with regard to Gregory’s writings, ascribing to him as genuine not only the Metaphrase on Ecclesiastes (henceforth referred to as the Metaphrase) and the Canonical Epistle, but also the Address of Thanksgiving to Origen (henceforth the Address), To Theopompus, and To Philagrius, for reasons which I shall give below. As doubtful or spurious I have included To Tatian, a Glossary on Ezekiel, and the famous Creed, which appears in Gregory of Nyssa’s Life of Gregory Thaumaturgus.”
(Michael Slusser, Fathers of the Church 98:5)

The last of the mentioned writings in this quotation, the Creed, is another title for the Declaration of Faith as it was titled in the Ante-Nicene Fathers. Here we see it’s authorship rejected again:

“The confession of faith attributed to him by Gregory of Nyssa is the latter’s own composition.”
(Fredrick W. Norris, Encyclopedia of Early Christianity, 2nd ed., pg. 499)

And yet again:

“L. Abramowski and P. Nautin called into doubt the authenticity, respectively, of the Exposition of Faith and the Panegyric to Origen, and consequently also the identification of the Wonder Worker with the Gregory who received of the letter of Origen handed down by the Philocalia. H. Crouzal attempted to reply to this devastating criticism, but with little success, since some of the arguments put forth by the other scholars were quite strong: the Exposition of Faith is certainly inauthentic in its last part, which belongs to the trinitarian debate in the 2nd half of the 4th c., and perhaps the whole work should be considered spurious”

(Manlio Simonetti, Encyclopedia of Ancient Christianity 2:188)