Bring the Book of Ur to Keeper Bel'dugur at the Apothecarium in the Undercity.
[player], Shadowfang Keep holds a book, the Book of Ur, which would be much prized in my collection. Ur was a great mage of Dalaran before the coming of the Scourge, his studies in other worlds are of much value to ... certain parties among the Forsaken.
Enter Shadowfang Keep and find the book. Bring it to me, and I will report your service to our Dark Lady...