If you have links to the source for this I would welcome them. I know that there are so-called Gnostic Gospels, and other documents referred to as pseudepigrapha by many scholars.
One of the most reliable researchers of that period of history was Alfred Edersheim which has a mammoth bibliography at the end. Here is a paragraph from his chapter on the Magi:
The story of the homage to the Infant Saviour by the Magi is told by St. Matthew, in language of which the brevity constitutes the chief difficulty. Even their designation is not free from ambiguity. The term Magi is used in the LXX., by Philo, Josephus, and by profane writers, alike in an evil and, so to speak, in a good sense1012 — in the former case as implying the practice of magical arts;1013 in the latter, as referring to the those Eastern (especially Chaldee) priest-sages, whose researches, in great measure as yet mysterious and unknown to us, seem to have embraced much deep knowledge, though not untinged with superstition. It is to these latter, that the Magi spoken of by St. Matthew must have belonged. Their number — to which, however, no importance attaches — cannot be ascertained.1014 Various suggestions have been made as to the country of ‘the East,’ whence they came. At the period in question the sacerdotal caste of the Medes and Persians was dispersed over various parts of the East,1015 and the presence in those lands of a large Jewish diaspora, through which they might, and probably would, gain knowledge of the great hope of Israel,1016 is sufficiently attested by Jewish history. The oldest opinion traces the Magi — though partially on insufficient grounds1017 — to Arabia. And there is this in favor of it, that not only the closest intercourse existed between Palestine and Arabia, but that from about 120 b.c. to the sixth century of our era, the kings of Yemen professed the Jewish faith.1018 For if, on the one hand, it seems unlikely, that Eastern Magi would spontaneously connect a celestial phenomenon with the birth of a Jewish king, evidence will, on the other hand, be presented to connect the meaning attached to the appearance of ‘the star’ at that particular time with Jewish expectancy of the Messiah. But we are anticipating.