The Book of EnochInteresting reading, especially once I knew the history. Sorry to post and run this morning but I've got to get to work. Check out the link. It will tell you more than I am able this morning.
This subject is exhaustively treated in a late 1800's book by John Fleming titled Fallen Angels and the Heroes of Mythology. Those interested can find it here: http://www.mcbryan.co.uk/docs.htm