The Book of Enoch, by R.H. Charles, [1917], at sacred-texts.com
LXIV. Vision of the fallen Angels in the Place of Punishment.
CHAPTER LXIV.
1. And other forms I saw hidden in that place. 2. I heard the voice of the angel saying: 'These are the angels who descended to the earth, and revealed what was hidden to the children of men and seduced the children of men into committing sin.'