Connection w/ 1 Enoch?
nDirection of dependence?
nJude on Enoch, vice versa, 3rd source?
nScraps of 1 Enoch at Qumran contain the quotation, so it predates Jude.
nQuote does fit naturally into 1 Enoch.
nOf course, Jude might be using some common tradition predating 1 Enoch.