That's how a part of Serbs was named Illyrians after Gad's son Arile, because that part of Gadites moved to the lands of Serbs, after having been exiled from Assyria and Egypt before that. This would also mean that among Serbs there were descendants of Shem, son of Noah, too, despite the fact that Serbs were in majority descendants of Tiras
I was able to download this book from another site and this is the whole point of this book. Not sure how accurate it is. Writer tries to connect the Serbs and the Jews all the way back to great flood. In my opinion this is true nonsense. As I listed through this book there is not concrete evidence that the Serbs are of Jewish origin. He rather connects us more closely to Iranians and Indians.
Anyhow, I learned nothing. I can't believe that this man has PHD and is professor at an American university.