The Book of Enoch (1 Enoch) is actually part of the Bible for the Ethiopian Orthodox Church. None of the other four are in any major formal canon. That said, as the article observes, many people today prefer to mix and match from inside and outside the canons to form their own personal set of scriptures.
I could quibble over some of the other details in the article. But I fully agree that everyone interested in the Bible (not just Christians) should read all five of these books: the Gospel of Thomas, 1 Enoch, the Infancy Gospel of Thomas, the Gospel of Mary, and the Acts of Paul and Thecla.
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